Core Curriculum Assessment Report 2012‐2013 Department Physics
Representative
Michael Bozack, James Hanson
Academic Year
2012_13
Course Name / number PHYS1600/1617, PHYS1610/1617
2.
SLO(s) being assessed: Student will..
SLO 10: Students will understand and appreciate methods and issues of science and technology.
3.
AGSC Content Area of Alignment:
Area III: Science and Math
4.
Assessment Method(s): [Explain how assessment for the measures associated with this SLO ‐ not grading for the course as a whole ‐ was conducted. You my cut/paste rubics for inclusion here, identify faculty reviewing committees, or identify specific kinds of test questions important to your method. Is this the method you initially planned to use? Provide a separate paragraph for each method].
The department has identified the following assessment methods: homework problems, laboratory experiences, classroom interactive sessions and test/exam questions. Faculty may elect to use any or all of these assessment methods to evaluate the effectiveness of their teaching. This format was approved by the CCGEC in 2010‐2011. The department has selected MasteringPhysics online assignment system as the preferred assessment method because of the availability of the national average data. The national average data provide a comparison tool to enable us to gauge our students’ performance against those of other ins tu ons across the country.In courses where there were mul ple sec ons with different instructors, the department committee has previously suggested that all instructors should use a common set of problems in MasteringPhysics to enable meaningful comparison of scores between different sections. These common sets of problems were provided to the instructors by the department committee before the start of each semester. However, some instructors preferred not to use MasteringPhysics for various reasons or to use their own set of ques ons.Most of the instructors teaching the PHYS 1600/1610 series of courses used MasteringPhysics as the assessment method. One instructor who taught PHYS1617 Honors Physics II used the final exam. The instructor for PHYS1607 did not do the required assessment.The department committee overseeing this course met on March 28, 2013, to discuss the results of those assessments carried out for the Fall 2012 semester. Data from the Spring 2013 semester will be discussed by the department commi ee in Fall 2013. The commi ee members were:Chin‐Che Tin (Chair)Yu LinDavid MaurerMinseo ParkBesides the commi ee members listed above, the commi ee chair also invited other faculty members teaching introductory physics courses to the mee ng to par cipate in the discussion.The following grading scale was used to determine competency level and this was based on typical scores obtained from assessments over the last few years. Competency Scale:MasteringPhysics Online Assignment:≥ (Na onal Average + 6%):Advanced Ability (Na onal Average 5%):Intermediate Ability≤ (Na onal Average – 6%):Basic Ability Non Comple on:Li le or No Abilityeg. If the national average score is 90%, then a score between 85 ‐ 65% would be considered Intermediate Ability. A score ≥ 96% would be considered Advanced Ability, and ≤ 84% would be Basic Ability.Quizzes/Test/Exam:≥ 85%:Advanced Ability 60 – 84%:Intermediate Ability 40 – 59%:Basic Ability≤ 39%:Li le or No AbilityIn reconciling the language of the measures within Student Learning Outcomes #10 with the topics normally covered in the physics courses, the department has chosen to adopt the following interpretations of the different measures. The department committee and instructors have used these interpretations as a general guideline in their choice of questions. The CCGEC commi ee should bear this in mind as they review the problems used in our assessments.Measure 1: Use ques ons involving fundamental principles of physics such as the conserva on laws. Measure 2: Use problems involving basic mathematical skills such as vector and scalar addition and subtraction, derivative Core Curriculum Assessment Report 2012‐2013 Department Physics
Representative
Michael Bozack, James Hanson
Academic Year
2012_13
Course Name / number PHYS1600/1617, PHYS1610/1617
and integration (for calculus‐based class), finding slope and area (both algebra and calculus‐based class), dot and cross products (calculus‐based class), and common experimental techniques. Measure 3: Deduce informa on from graphical, tabulated, or experimental data. Measure 4: Problems showing connec ons between science and society involving topics such as energy, health, etc.Measure 5: Problems requiring knowledge and demonstra ng analy cal skills especially in those areas not covered above.
5.
Findings: What assessment data did each assessment method produce?
PHYS 1600 Fall 2012:
‐ Average scores for Instructors F, G, and H were 87.0%, 81.1%, and 86.2%, respectively. Although, all were lower than the national average, the scores for Instructors F and H were within the limits to qualify for Intermediate Ability, but the score for Instructor G was in the scale of Basic Ability. PHYS 1600 Spring 2013:
‐ Average score for Instructor F was 94.9% which was comparable to the national average of 93.0%. PHYS 1610 Fall 2012:
‐ Average scores for Instructors I, L, and J were 96.1%, 96.5%, and 95.5%, respectively. All were comparable with the national average of 94.29%. PHYS 1610 Spring 2013:
‐ Average score for Instructor I was 90.3% which was lower than the national average but still within the limits for Intermediate Ability. Instructor I used the questions from the common set of questions provided by the committee.
‐ Average score for Instructor J was 95.5% which was higher than the national average of 91.59%. Instructor J only used some of the questions provided by the committee.
PHYS 1607 Fall 2012:
‐ No data
PHYS 1617 Spring 2013:
‐ Instructor M used final exam as the assessment method. Average score was 71% which was comparable to the typical test scores for introductory physics courses. Instructor I’s comments:
The results from our assessment indicate that students are learning valuable information in the course. Around 88% of the students know well about the historical foundations of the physics and display advance understanding of the basic physics principles and utilize them to analyze and solve problems (Measures 1, 2 and 5). Around 95% of the students have strong technical skill to conduct and interpret experiment and natural phenomena (Measure 3) and know well about the societal impact (Measure 4). We will use these results to indicate areas in which we can continue to strengthen the course and improve our abilities to enhance the students’ learning experiences.
Instructor J’s comments:
I learned some things from the student comments in the University Evaluation system and from the results of the final exam. Based on that, I expect to have enhanced learning next year.
Core Curriculum Assessment Report 2012‐2013 Department Physics
Representative
Michael Bozack, James Hanson
Academic Year
2012_13
Course Name / number PHYS1600/1617, PHYS1610/1617
Attachment name: PHYS1600‐1610‐1617 F12‐S13.pdf
6.
7.
Based on the comprehensive rubric for the appropriate SLO(s), indicate the extent of competency of the average student who has completed this core course in each learning outcome assigned to it:
SLO
Level of Ability
SLO 10
intermediate
How did you (or will you) use the findings for improvement?
[What questions / issues / concerns did your data raise for the faculty teaching the course? What discussion did the faculty have about the findings? What future actions to improve student attainment of this outcome will the department / program take as a result of this analysis?]
Scores for PHYS1600 Fall 2012 were not satisfactory for they were lower than the national average. The score for Instructor G was significantly lower to earn a rating of "Basic Ability". Instructors should ask the teaching assistants to give a brief discussion of the problems to better prepare the students for the assignments. Instructors should take note of the shortcomings in the various measures and to tailor their lectures accordingly in future classes.
Scores for other courses were generally within the limits of the national average.
8.
Additional Comments:
[What else would you like the Committee to know about your assessment of this course or plans for the future?]
Actual names of the instructors were not used because we believe that these assessments should not be used as the assessment of the instructors.
The department continues to have strong reservations about the language used in the description of the various measures constituting SLO#10. The wording of the measures does not match with the typical questions normally used in physics courses. The faculty believes that the department should be the one to determine the proper questions to use in the assessments. The instructors were therefore asked to use their best judgment in choosing the appropriate questions with the broad intents of the measures in mind. The department believes that assessments do help to provide insights into our teaching methods and their effectiveness. However, the department committee would suggest modifying the wording of the measures to make them more inline with our courses and to make the exercise more meaningful. For future assessments in large classes, the department committee would consider a different approach closer to a formal testing method in order to provide a more accurate measure of the competency level of the students.
9.
Committee Comments:
PHYS 1600
ENGINEERING PHYSICS I
PHYS 1600 – Engineering Physics I
Fall 2012
Instructors: F, G, H
Number of Students: 142(F), 96 (G), 209 (H)
Mode of Assessment: Assignment (MasteringPhysics)
% Complete
Measure
1
2
3
4
5
%
National
Score
% Average Score
Problem
1.1
1.2
1.3
1.4
1.5
2.1
2.2
2.3
2.4
2.5
3.1
3.2
3.3
3.4
3.5
4.1
4.2
4.3
4.4
4.5
5.1
5.2
5.3
5.4
5.5
Average
Average
Competency Level
Instructor
F
Instructor
G
Instructor
H
91.6
79.7
88.1
67.8
84.6
90.9
91.6
84.6
81.1
74.1
88.8
90.2
86.0
88.1
58.7
90.2
80.4
88.1
79.7
70.6
88.8
87.4
79.0
72.7
67.8
82.0
87.6
80
82.8
62.8
62.8
91
84.8
84.8
62.3
75.2
89
87.6
82.8
54.2
70
67.9
67.4
64.2
61.1
74.7
42.8
89.7
77.2
83.4
75.9
53.8
82.7
82.8
77.9
43.4
75.8
66.3
55.3
70
73.7
63.7
64.7
72.1
66.3
48.9
65.0
Instructor F
Instructor G
Instructor H
85.2
89.8
82.3
75.7
91.0
91.2
89.1
85.3
89.7
89.7
91.3
77.5
86.1
95.0
79.5
92.7
88.0
90.5
88.3
91.3
83.5
80.8
92.7
85.2
83.5
87.0
Intermediate
Ability
85.8
72.7
84.2
77.9
88.6
87.9
88.4
74.7
73.2
88.3
93.8
78.5
89.2
61.1
70.4
67.8
79.9
90.0
89.3
92.1
83.0
39.3
86.2
78.4
88.4
84.4
81.1
Basic
Ability
96.0
93.9
92.8
83.0
90.1
93.7
90.0
88.3
94.6
85.5
78.6
90.0
88.0
66.3
86.2
Intermediate
Ability
92.8
92.8
99.2
89.7
95.3
94.9
96.5
87.0
94.9
92.5
96.7
89.0
95.4
95.6
92.6
96.2
94.6
94.7
91.3
88.0
94.3
89.4
95.5
89.7
89.0
93.1
PROBLEMS:
Measure 1:
Articulate the philosophical and historical foundations of modern science.
1.1
Problem 2.20
A rock is tossed straight up with a velocity of 20 m/s. When it returns, it falls into a hole 10-m deep.
a) What is the rock's velocity as it hits the bottom of the hole?
b) How long is the rock in the air, from the instant it is released until it hits the bottom of the hole?
1.2
Problem 9.42
One billiard ball is shot east at 1.8m/s. A second, identical billiard ball is shot west at 1.0 m/s. The balls
have a glancing collision, not a head-on collision, deflecting the second ball by 90°and sending it north at
1.45m/s .
a) What are the speed and direction of the first ball after the collision?
b) What is the direction of the first ball after the collision? Give the direction as an angle south of east.
1.3
Problem 10.4
a) What is the kinetic energy of a 1200kg car traveling at a speed of 30 m/s (~ 65 mph)?
b) From what height would the car have to be dropped to have this same amount of kinetic energy just
before impact?
c) Does your answer to part (b) depend on the car’s mass?
1.4
Problem 12.80
A 230 g, 46.0-cm-diameter turntable rotates on frictionless bearings at 63.0 rpm. A 25.0g block sits at the
center of the turntable. A compressed spring shoots the block radically outward along a frictionless
groove in the surface of the turntable. What is the turntable's rotation angular velocity when the block
reaches the outer edge?
1.5
Problem 14.51
It is said that Galileo discovered a basic principle of the pendulum-that the period is independent of the
amplitude-by using his pulse to time the period of swinging lamps in the cathedral as they swayed in the
breeze. Suppose that one oscillation of a swinging lamp takes 5.5s.
a) How long is the lamp chain?
b) What maximum speed does the lamp have if its maximum angle from vertical is 3.0º?
Measure 2:
Understand the scientific method and demonstrate an ability to apply it
across a variety of situations.
2.1
Problem 2.11
The figure shows the velocity graph of a particle moving along the x-axis. Its initial position is x0 =2 m at
t0 = m. At t = 3 s, what are the particle's (a) position, (b) velocity, and (c) acceleration?
2.2
Problem 2.31
The position of a particle is given by the function x = (2t3 – 9t2 + 12) where t is in m/s.
a) At what time or times is vx = 0 m/s?
b) What is the particle's position at these times?
c) What is the particle's acceleration at these times?
2.3
Problem 3.42
The figure shows three ropes tied together in a knot. One of your friends
pulls on a rope with 3.0 units of force and another pulls on a second rope
with 5.0 units of force.
a) How hard must you pull on the third rope to keep the knot from
moving?
b) In what direction must you pull on the third rope to keep the knot from
moving?
2.4
Problem 11.8
a) How much work is done by the force F = (-3.5 i - 5.0 j) N on a particle that moves through
displacement Δr = - 3.3 i m?
b) How much work is done by the force F = (-3.5 i - 5.0 j) N on a particle that moves through Δr = 3.3 i
- 2.0 j) m?
2.5
Problem 12.40
Vector A = 5 i + 3 j and vector B = 5 i - 6 j + 4 k.
a) What is the cross product A × B? Find the x-component.
b) Find the y-component.
c) Find the z-component.
Measure 3:
Demonstrate an ability to conduct, and interpret the results of experiments
aimed at better understanding natural phenomena.
3.1
Problem 2.29
A block is suspended from a spring, pulled down, and released. The block's position-versus-time graph is
shown in the figure .
a) At what times is the velocity zero from t = 0 to 4 s?
b) At what times is the velocity most positive from t = 0 to 4 s?
c) At what times is the velocity most negative from t = 0 to 4 s?
3.2
Problem 4.45
A tennis player hits a ball 2.0 m above the ground. The ball leaves his racquet with a speed of 25.0 m/s at
an angle 5.5° above the horizontal. The horizontal distance to the net is 7.0 m, and the net is 1.0 m high.
a) Does the ball clear the net?
b) By how much?
3.3
Problem 6.15
The figure shows the velocity graph of a 77 kg passenger in an elevator.
a) What is the passenger's apparent weight at t =1 s?
b) What is the passenger's apparent weight at t = 5 s?
c) What is the passenger's apparent weight at t = 9 s?
3.4
Problem 10.20
A student places her 430 g physics book on a frictionless table. She pushes the book against a spring,
compressing the spring by 9.10 cm, then releases the book.
What is the book's speed as it slides away? The spring constant is 1850 N/m .
3.5
Problem 14.35
Astronauts in space cannot weigh themselves by standing on a bathroom scale. Instead, they determine
their mass by oscillating on a large spring. Suppose an astronaut attaches one end of a large spring to her
belt and the other end to a hook on the wall of the space capsule. A fellow astronaut then pulls her away
from the wall and releases her. The spring's length as a function of time is shown in the figure .
a) What is her mass if the spring constant is 230 N/m?
b) What is her speed when the spring's length is 1.2m?
Measure 4:
Understand major issues and problems facing modern science and
technology, including issues related to ethics, cultural values, public policies,
and the impact of human activity upon the planet.
4.1
Problem 2.43
You are driving to the grocery store at 20 m/s. You are 110 m from an intersection when the traffic light
turns red. Assume that your reaction time is 0.50 s and that your car brakes with constant acceleration.
a) How far are you from the intersection when you begin to apply the brakes?
b) What acceleration will bring you to rest right at the intersection?
c) How long does it take you to stop after the light turns red?
4.2
Problem 6.34
Seat belts and air bags save lives by reducing the forces exerted on the driver and passengers in an
automobile collision. Cars are designed with a "crumple zone" in the front of the car. In the event of an
impact, the passenger compartment decelerates over a distance of about 1 m as the front of the car
crumples. An occupant restrained by seat belts and air bags decelerates with the car. By contrast, an
unrestrained occupant keeps moving forward with no loss of speed (Newton's first law!) until hitting the
dashboard or windshield. These are unyielding surfaces, and the unfortunate occupant then decelerates
over a distance of only about 5 mm.
a) A 60 kg person is in a head-on collision. The car's speed at impact is 20 m/s. Estimate the net force
on the person if he or she is wearing a seat belt and if the air bag deploys.
b) Estimate the net force that ultimately stops the person if he or she is not restrained by a seat belt or air
bag.
c) What is the force in part (a) in terms of the person's weight?
d) What is the force in part (b) in terms of the person's weight?
4.3
Problem 8.8
A highway curve of radius 560 m is designed for traffic moving at a speed of 73.0 km/hr. What is the
correct banking angle of the road?
4.4
Problem 9.37
Most geologists believe that the dinosaurs became extinct 65 million years ago when a large comet or
asteroid struck the earth, throwing up so much dust that the sun was blocked out for a period of many
months. Suppose an asteroid with a diameter of 2.0 km and a mass of 1.0×1013 kg hits the earth with an
impact speed of 4.0×104 m/s.
a) What is the earth's recoil speed after such a collision? (Use a reference frame in which the earth was
initially at rest.)
b) What percentage is this of the earth's speed around the sun? (Use the astronomical data in the
textbook.)
4.5
Problem 11.65
In a hydroelectric dam, water falls 35.0m and then spins a turbine to generate electricity.
a) What is ΔU of 1.0 kg of water?
b) Suppose the dam is 80% efficient at converting the water's potential energy to electrical energy. How
many kilograms of water must pass through the turbines each second to generate 45.0 MW of
electricity? This is a typical value for a small hydroelectric dam.
Measure 5:
Demonstrate knowledge in one area of science, including understanding its
basic principles, laws, and theories.
5.1
Problem 4.16
When the moving sidewalk at the airport is broken, as it often seems to be, it takes you 50 s to walk from
your gate to baggage claim. When it is working and you stand on the moving sidewalk the entire way,
without walking, it takes 90 s to travel the same distance. How long will it take you to travel from the gate
to baggage claim if you walk while riding on the moving sidewalk?
5.2
Problem 7.40
The coefficient of kinetic friction between the 2.0 kg block in figure and the table is 0.270.
What is the acceleration of the 2.0 kg block?
5.3
Problem 9.60
The nucleus of the polonium isotope 214Po (mass 214 u) is radioactive and decays by emitting an alpha
particle (a helium nucleus with mass 4 u). Laboratory experiments measure the speed of the alpha particle
to be 1.91×107 m/s. Assuming the polonium nucleus was initially at rest, what is the recoil speed of the
nucleus that remains after the decay?
5.4
Problem 15.64
Air flows through the tube shown in the figure. Assume that air
is an ideal fluid.
a) What is the air speed v1 at point 1?
b) What is the air speed v2 at point 2?
c) What is the volume flow rate?
5.5
Problem 21.52
A 1.0-m-tall vertical tube is filled with 20°C water. A tuning fork vibrating at 571 Hz is held just over the
top of the tube as the water is slowly drained from the bottom. At what water heights, measured from the
bottom of the tube, will there be a standing wave in the tube above the water?
PHYS 1600 – Engineering Physics I
Spring 2013
Instructor: F
Number of Students: 245
Mode of Assessment: Assignment (MasteringPhysics)
Measures
1
2
3
4
5
Problems
1.1
1.2
1.3
1.4
1.5
2.1
2.2
2.3
2.4
2.5
3.1
3.2
3.3
3.4
4.1
4.2
4.3
4.4
4.5
5.1
5.2
5.3
5.4
5.5
Average
Average Competency Level
% Complete
% Average Score
92.9
84.5
93.3
76.6
79.4
97.2
92.9
84.9
91.7
85.7
93.7
91.3
89.3
74.6
92.1
81.3
90.1
84.5
88.9
94.4
88.9
84.1
79.8
68.3
86.7
93.8
94.1
99.6
92.7
96.3
94.1
96.6
92.5
97.8
96.5
92.2
95.4
97.8
89.9
97.8
94.0
94.7
93.0
94.2
97.9
95.1
96.7
96.0
87.8
94.9
Intermediate
Ability
% National Score
92.8
92.8
99.2
89.7
95.3
94.9
96.5
87.0
94.9
92.5
89.0
95.4
95.6
92.6
96.2
94.6
94.7
91.3
88.0
94.3
89.4
95.5
89.7
89.0
93.0
PROBLEMS:
Measure 1:
Articulate the philosophical and historical foundations of modern science.
1.1
Problem 2.20
A rock is tossed straight up with a velocity of 20 m/s. When it returns, it falls into a hole 10-m deep.
a) What is the rock's velocity as it hits the bottom of the hole?
b) How long is the rock in the air, from the instant it is released until it hits the bottom of the hole?
1.2
Problem 9.42
One billiard ball is shot east at 1.8m/s. A second, identical billiard ball is shot west at 1.0 m/s. The balls
have a glancing collision, not a head-on collision, deflecting the second ball by 90°and sending it north at
1.45m/s .
a) What are the speed and direction of the first ball after the collision?
b) What is the direction of the first ball after the collision? Give the direction as an angle south of east.
1.3
Problem 10.4
a) What is the kinetic energy of a 1200kg car traveling at a speed of 30 m/s (~ 65 mph)?
b) From what height would the car have to be dropped to have this same amount of kinetic energy just
before impact?
c) Does your answer to part (b) depend on the car’s mass?
1.4
Problem 12.80
A 230 g, 46.0-cm-diameter turntable rotates on frictionless bearings at 63.0 rpm. A 25.0g block sits at the
center of the turntable. A compressed spring shoots the block radically outward along a frictionless
groove in the surface of the turntable. What is the turntable's rotation angular velocity when the block
reaches the outer edge?
1.5
Problem 14.51
It is said that Galileo discovered a basic principle of the pendulum-that the period is independent of the
amplitude-by using his pulse to time the period of swinging lamps in the cathedral as they swayed in the
breeze. Suppose that one oscillation of a swinging lamp takes 5.5s.
a) How long is the lamp chain?
b) What maximum speed does the lamp have if its maximum angle from vertical is 3.0º?
Measure 2:
Understand the scientific method and demonstrate an ability to apply it
across a variety of situations.
2.1
Problem 2.11
The figure shows the velocity graph of a particle moving along the x-axis. Its initial position is x0 =2 m at
t0 = m. At t = 3 s, what are the particle's (a) position, (b) velocity, and (c) acceleration?
2.2
Problem 2.31
The position of a particle is given by the function x = (2t3 – 9t2 + 12) where t is in m/s.
a) At what time or times is vx = 0 m/s?
b) What is the particle's position at these times?
c) What is the particle's acceleration at these times?
2.3
Problem 3.42
The figure shows three ropes tied together in a knot. One of your friends pulls on a rope with 3.0 units of
force and another pulls on a second rope with 5.0 units of force.
a) How hard must you pull on the third rope to keep the knot from moving?
b) In what direction must you pull on the third rope to keep the knot from moving?
2.4
Problem 11.8
a) How much work is done by the force F = (-3.5 i - 5.0 j) N on a particle that moves through
displacement Δr = - 3.3 i m?
b) How much work is done by the force F = (-3.5 i - 5.0 j) N on a particle that moves through Δr = 3.3 i
- 2.0 j) m?
2.5
Problem 12.40
Vector A = 5 i + 3 j and vector B = 5 i - 6 j + 4 k.
a) What is the cross product A × B? Find the x-component.
b) Find the y-component.
c) Find the z-component.
Measure 3:
Demonstrate an ability to conduct, and interpret the results of experiments
aimed at better understanding natural phenomena.
3.1
Problem 4.45
A tennis player hits a ball 2.0 m above the ground. The ball leaves his racquet with a speed of 25.0 m/s at
an angle 5.5° above the horizontal. The horizontal distance to the net is 7.0 m, and the net is 1.0 m high.
a) Does the ball clear the net?
b) By how much?
3.2
Problem 6.15
The figure shows the velocity graph of a 77 kg passenger in an elevator.
a) What is the passenger's apparent weight at t =1 s?
b) What is the passenger's apparent weight at t = 5 s?
c) What is the passenger's apparent weight at t = 9 s?
3.3
Problem 10.20
A student places her 430 g physics book on a frictionless table. She pushes the book against a spring,
compressing the spring by 9.10 cm, then releases the book.
What is the book's speed as it slides away? The spring constant is 1850 N/m .
3.4
Problem 14.35
Astronauts in space cannot weigh themselves by standing on a
bathroom scale. Instead, they determine their mass by oscillating on
a large spring. Suppose an astronaut attaches one end of a large
spring to her belt and the other end to a hook on the wall of the
space capsule. A fellow astronaut then pulls her away from the wall
and releases her. The spring's length as a function of time is shown
in the figure .
a) What is her mass if the spring constant is 230 N/m?
b) What is her speed when the spring's length is 1.2m?
Measure 4:
Understand major issues and problems facing modern science and
technology, including issues related to ethics, cultural values, public policies,
and the impact of human activity upon the planet.
4.1
Problem 2.43
You are driving to the grocery store at 20 m/s. You are 110 m from an intersection when the traffic light
turns red. Assume that your reaction time is 0.50 s and that your car brakes with constant acceleration.
a) How far are you from the intersection when you begin to apply the brakes?
b) What acceleration will bring you to rest right at the intersection?
c) How long does it take you to stop after the light turns red?
4.2
Problem 6.34
Seat belts and air bags save lives by reducing the forces exerted on the driver and passengers in an
automobile collision. Cars are designed with a "crumple zone" in the front of the car. In the event of an
impact, the passenger compartment decelerates over a distance of about 1 m as the front of the car
crumples. An occupant restrained by seat belts and air bags decelerates with the car. By contrast, an
unrestrained occupant keeps moving forward with no loss of speed (Newton's first law!) until hitting the
dashboard or windshield. These are unyielding surfaces, and the unfortunate occupant then decelerates
over a distance of only about 5 mm.
a) A 60 kg person is in a head-on collision. The car's speed at impact is 20 m/s. Estimate the net force
on the person if he or she is wearing a seat belt and if the air bag deploys.
b) Estimate the net force that ultimately stops the person if he or she is not restrained by a seat belt or air
bag.
c) What is the force in part (a) in terms of the person's weight?
d) What is the force in part (b) in terms of the person's weight?
4.3
Problem 8.8
A highway curve of radius 560 m is designed for traffic moving at a speed of 73.0 km/hr. What is the
correct banking angle of the road?
4.4
Problem 9.37
Most geologists believe that the dinosaurs became extinct 65 million years ago when a large comet or
asteroid struck the earth, throwing up so much dust that the sun was blocked out for a period of many
months. Suppose an asteroid with a diameter of 2.0 km and a mass of 1.0×1013 kg hits the earth with an
impact speed of 4.0×104 m/s.
a) What is the earth's recoil speed after such a collision? (Use a reference frame in which the earth was
initially at rest.)
b) What percentage is this of the earth's speed around the sun? (Use the astronomical data in the
textbook.)
4.5
Problem 11.65
In a hydroelectric dam, water falls 35.0m and then spins a turbine to generate electricity.
a) What is ΔU of 1.0 kg of water?
b) Suppose the dam is 80% efficient at converting the water's potential energy to electrical energy. How
many kilograms of water must pass through the turbines each second to generate 45.0 MW of
electricity? This is a typical value for a small hydroelectric dam.
Measure 5:
Demonstrate knowledge in one area of science, including understanding its
basic principles, laws, and theories.
5.1
Problem 4.16
When the moving sidewalk at the airport is broken, as it often seems to be, it takes you 50 s to walk from
your gate to baggage claim. When it is working and you stand on the moving sidewalk the entire way,
without walking, it takes 90 s to travel the same distance. How long will it take you to travel from the gate
to baggage claim if you walk while riding on the moving sidewalk?
5.2
Problem 7.40
The coefficient of kinetic friction between the 2.0 kg block in figure and the table is 0.270.
What is the acceleration of the 2.0 kg block?
5.3
Problem 9.60
The nucleus of the polonium isotope 214Po (mass 214 u) is radioactive and decays by emitting an alpha
particle (a helium nucleus with mass 4 u). Laboratory experiments measure the speed of the alpha particle
to be 1.91×107 m/s. Assuming the polonium nucleus was initially at rest, what is the recoil speed of the
nucleus that remains after the decay?
5.4
Problem 15.64
Air flows through the tube shown in the figure. Assume that air is an ideal fluid.
a) What is the air speed v1 at point 1?
b) What is the air speed v2 at point 2?
c) What is the volume flow rate?
5.5
Problem 21.52
A 1.0-m-tall vertical tube is filled with 20°C water. A tuning fork vibrating at 571 Hz is held just over the
top of the tube as the water is slowly drained from the bottom. At what water heights, measured from the
bottom of the tube, will there be a standing wave in the tube above the water?
PHYS 1610
ENGINEERING PHYSICS II
PHYS 1610 – Engineering Physics II
Fall 2012
Instructors: I, L, J
Number of Students: 126 (I), 73 (L), 145 (J)
Mode of Assessment: Assignment (MasteringPhysics)
Measures
Problems
1
1.1
1.2
1.3
1.4
1.5
2.1
2.2
2.3
2.4
3.1
3.2
3.3
3.4
3.5
4.1
4.2
4.3
4.4
4.5
5.1
5.2
5.3
5.4
2
3
4
5
Average
Average
Competency Level
% Complete
Instructor Instructor Instructor
I
L
J
88.8
87.7
90.4
93.2
77.3
92.2
90.9
81.8
90.9
85.1
82.4
86.3
77.9
86.4
84.9
75.3
89.6
86.3
86.4
86.3
77.3
73.4
84.8
79.5
75.3
85.6
87.7
80.5
87.2
86.3
71.2
78.1
85.1
66.4
37
77.3
94.4
90.4
83.1
83.2
79.5
76.6
68.8
78.1
80.5
82.5
83.8
88.8
87.7
79.2
83.6
81.9
81.3
% Average Score
Instructor Instructor Instructor
I
L
J
94.6
93.8
99.1
100
99.2
92.6
95.0
93.7
91.4
93.5
90.8
91.3
95.8
98.1
96.8
94.8
98.2
98.4
96.3
98.4
99.2
94.7
89.6
94.8
94.8
98.1
97.7
97.6
98.2
98.4
97.8
96.5
100
94
90.7
96.6
97.5
100
99.2
96.2
96.6
94.9
97.1
96.5
96.0
94.0
90.7
95.5
96.9
95.9
96.1
96.5
95.48
Intermediate Ability
%
National
Score
91.92
95.47
94.89
97.80
92.78
94.48
97.79
95.23
87.88
92.78
97.49
86.56
91.83
97.68
94.89
95.15
92.42
99.92
96.77
88.76
91.25
99.63
92.72
94.29
PROBLEMS:
Measure 1:
Articulate the philosophical and historical foundations of modern science.
1.1
A 20-cm-diameter cylinder that is 40 cm long contains 50 g of oxygen gas at 20 ºC.
a) How many moles of oxygen are in the cylinder?
b) How many oxygen molecules are in the cylinder?
c) What is the number density of the oxygen?
d) What is the reading of a pressure gauge attached to the tank?
1.2
Light from a sodium lamp (λ = 589nm) illuminates two narrow slits. The fringe spacing on a screen
150cm behind the slits is 4.0 mm. What is the spacing (in mm) between the two slits?
1.3
A plastic rod that has been charged to -18 nC touches a metal sphere. Afterward, the rod's charge is -9.0
nC.
a) What kind of charged particle was transferred between the rod and the sphere, and in which direction?
That is, did it move from the rod to the sphere or from the sphere to the rod?
b) How many charged particles were transferred?
1.4
What is the net electric force on charge A in the figure?
1.5
In a classical model of the hydrogen atom, the electron orbits the proton in a circular orbit of radius
0.053nm. What is the orbital frequency? The proton is so much more massive than the electron that you
can assume the proton is at rest.
Measure 2:
Understand the scientific method and demonstrate an ability to apply it
across a variety of situations.
2.1
a) What is the magnitude of the force F on the 1.0 nC charge in the figure ?
b) What is the direction of the force F on the 1.0 nC charge in the figure?
2.2
Charge Q is uniformly distributed along a thin, flexible rod of length L. The rod is then bent into the
semicircle shown in the figure.
a) Find an expression for the electric field E at the center of the semicircle.
b) Evaluate the field strength if L = 10cm and Q = 30nC.
2.3
A proton moves in the magnetic field B = 0.50i T with a speed of 1.0 × 107m/s in the directions shown in
the figure. For each, what is magnetic force F on the proton?
a) Express vector F in the form Fx, Fy, Fz, where the x, y, and z components are separated by commas.
b) Express vector F in the form Fx, Fy, Fz, where the x, y, and z components are separated by commas.
2.4
A 40-turn, 4.0-cm-diameter coil with R = 0.40Ω surrounds a 3.0-cm-diameter solenoid. The solenoid is 20
cm long and has 200 turns. The 60Hz current through the solenoid is I = Io sin(2πft). What is Io if the
maximum induced current in the coil is 0.20A?
Measure 3:
Demonstrate an ability to conduct, and interpret the results of experiments
aimed at better understanding natural phenomena.
3.1
The solar corona is a very hot atmosphere surrounding the visible surface of the sun. X-ray emissions
from the corona show that its temperature is about 2×106 K. The gas pressure in the corona is about 0.03
Pa. Estimate the number density of particles in the solar corona.
3.2
The wings of some beetles have closely spaced parallel lines of melanin, causing the wing to act as a
reflection grating. Suppose sunlight shines straight onto a beetle wing. If the melanin lines on the wing
are spaced 2.8 μm apart, what is the first-order diffraction angle for green light (λ = 550 nm)?
3.3
The figure is an edge view of three charged
metal electrodes. Draw a graph of V versus x
over the region 0 x 3 cm. Hint: Assume that
V = 0 V at x = 0 cm.
3.4
A 90μF capacitor that had been charged to 30V is discharged through a
resistor. The figure shows the capacitor voltage as a function of time.
What is the value of the resistance?
3.5
The aurora is caused when electrons and protons, moving in the earth's magnetic field of ≈ 5×10-5 T,
collide with molecules of the atmosphere and cause them to glow.
a) What is the radius of the cyclotron orbit for an electron with speed 1.0 × 106 m/s?
b) What is the radius of the cyclotron orbit for a proton with speed 5.0 × 104 m/s?
Measure 4:
Understand major issues and problems facing modern science and
technology, including issues related to ethics, cultural values, public policies,
and the impact of human activity upon the planet.
4.1
On average, each person in the industrialized world is responsible for the emission of 10,000 kg of carbon
dioxide CO2 every year. This includes CO2 that you generate directly, by burning fossil fuels to operate
your car or your furnace, as well as CO2 generated on your behalf by electric generating stations and
manufacturing plants. CO2 is a greenhouse gas that contributes to global warming. If you were to store
your yearly CO2 emissions in a cube at STP, how long would each edge of the cube be?
4.2
A typical nuclear reactor generates 1000MW (1000 MJ/s) of electrical energy. In doing so, it produces
2000MW of "waste heat" that must be removed from the reactor to keep it from melting down. Many
reactors are sited next to large bodies of water so that they can use the water for cooling. Consider a
reactor where the intake water is at 18 ºC. State regulations limit the temperature of the output water to
30ºC so as not to harm aquatic organisms. How many liters of cooling water have to be pumped through
the reactor each minute?
4.3
A typical coal-fired power plant burns 350 metric tons of coal every hour to generate 750MW of
electricity. 1 metric ton = 1000 kg. The density of coal is 1500 kg/m3 and its heat of combustion is
28MJ/kg. Assume that all heat is transferred from the fuel to the boiler and that all the work done in
spinning the turbine is transformed into electrical energy.
a) Suppose the coal is piled up in a 9.00m × 11.0m room. How tall must the pile be to operate the plant
for one day?
b) What is the power plant's thermal efficiency?
4.4
Energy experts tell us to replace regular incandescent lightbulbs with compact fluorescent bulbs, but it
seems hard to justify spending $15 on a lightbulb. A 60W incandescent bulb costs 50 cents. and has a
lifetime of 1000 hours. A 15 W compact fluorescent bulb produces the same amount of light as a 60W
incandescent bulb and is intended as a replacement. It costs $15 and has a lifetime of 10,000 hours.
Compare the life-cycle costs of 60W incandescent bulbs to 15W compact fluorescent bulbs. The lifecycle cost of an object is the cost of purchasing it plus the cost of fueling and maintaining it over its
useful life. Which is the cheaper source of light and which the more expensive? Assume that electricity
costs 0.10 dollars/kWh.
4.5
One possible concern with MRI (magnetic resonance imaging) is turning the magnetic field on or off too
quickly. Bodily fluids are conductors, and a changing magnetic field could cause electric currents to flow
through the patient. Suppose a typical patient has a maximum cross-section area of 6.7×10−2 m2. What is
the smallest time interval in which a 5.6T magnetic field can be turned on or off if the induced emf
around the patient's body must be kept to less than 0.12V?
Measure 5:
Demonstrate knowledge in one area of science, including understanding its
basic principles, laws, and theories.
5.1
A monatomic gas follows the process 1→2→3shown in the figure.
a) How much heat is needed for process 1→2?
b) How much heat is needed for process 2→3?
5.2
A spherically symmetric charge distribution produces the electric field E
= (4900 r2) er N/C, where r is in m.
a) What is the electric field strength at r = 25.0 cm?
b) What is the electric flux through a 38.0-cm-diameter spherical surface that is concentric with the
charge distribution?
c) How much charge is inside this 38.0-cm-diameter spherical surface?
5.3
A -2.0nC charge and a 2.0nC charge are located on the x-axis at x = -1.0cm and x = +1.0cm, respectively.
a) At what position or positions on the x -axis is the electric field zero?
b) At what position or positions on the x -axis is the electric potential zero?
5.4
What power is dissipated by the 2Ω resistor in the figure?
PHYS 1610 – Engineering Physics II
Spring 2013
Instructor: I
Number of Students: 217
Mode of Assessment: Assignment (MasteringPhysics)
Measures
1
2
3
4
5
Problems
1.1
1.2
1.3
1.4
1.5
2.1
2.2
2.3
3.1
3.2
3.3
3.4
3.5
4.1
4.2
4.3
5.1
5.2
5.3
5.4
Average
Average
Competency Level
%
Complete
77.5
79.7
94.3
86.8
79.7
89.9
84.6
75.8
84.1
80.2
82.8
78.9
70.0
89.9
76.7
86.8
88.1
81.1
78.4
74.9
82.0
%
Average Score
85.8
99.4
88.1
76.6
93.7
90.4
82.0
89.2
96.9
99.5
95.5
87.2
87.1
98.0
96.6
95.4
93.1
84.8
89.8
77.1
90.3
Intermediate
Ability
% National
Score
91.92
95.47
94.89
97.80
92.78
94.48
97.79
95.23
92.78
97.49
96.90
91.83
91.23
94.89
95.15
92.42
91.25
93.51
94.90
92.72
94.27
PROBLEMS:
Measure 1:
Articulate the philosophical and historical foundations of modern science.
1.1
A 20-cm-diameter cylinder that is 40 cm long contains 50 g of oxygen gas at 20 ºC.
a) How many moles of oxygen are in the cylinder?
b) How many oxygen molecules are in the cylinder?
c) What is the number density of the oxygen?
d) What is the reading of a pressure gauge attached to the tank?
1.2
Light from a sodium lamp (λ = 589nm) illuminates two narrow slits. The fringe spacing on a screen
150cm behind the slits is 4.0 mm. What is the spacing (in mm) between the two slits?
1.3
A plastic rod that has been charged to -18 nC touches a metal sphere. Afterward, the rod's charge is -9.0
nC.
a) What kind of charged particle was transferred between the rod and the sphere, and in which direction?
That is, did it move from the rod to the sphere or from the sphere to the rod?
b) How many charged particles were transferred?
1.4
What is the net electric force on charge A in the figure?
1.5
In a classical model of the hydrogen atom, the electron orbits the proton in a circular orbit of radius
0.053nm. What is the orbital frequency? The proton is so much more massive than the electron that you
can assume the proton is at rest.
Measure 2:
Understand the scientific method and demonstrate an ability to apply it
across a variety of situations.
2.1
a) What is the magnitude of the force F on the 1.0 nC charge in the figure ?
b) What is the direction of the force F on the 1.0 nC charge in the figure?
2.2
Charge Q is uniformly distributed along a thin, flexible rod of length L. The rod is
then bent into the semicircle shown in the figure.
a) Find an expression for the electric field E at the center of the semicircle.
b) Evaluate the field strength if L = 10cm and Q = 30nC.
2.3
A proton moves in the magnetic field B = 0.50i T with a speed of 1.0 × 107m/s in the directions shown in
the figure. For each, what is magnetic force F on the proton?
a) Express vector F in the form Fx, Fy, Fz, where the x, y, and z components are separated by commas.
b) Express vector F in the form Fx, Fy, Fz, where the x, y, and z components are separated by commas.
Measure 3:
Demonstrate an ability to conduct, and interpret the results of experiments
aimed at better understanding natural phenomena.
3.1
The solar corona is a very hot atmosphere surrounding the visible surface of the sun. X-ray emissions
from the corona show that its temperature is about 2×106 K. The gas pressure in the corona is about 0.03
Pa. Estimate the number density of particles in the solar corona.
3.2
The wings of some beetles have closely spaced parallel lines of melanin, causing the wing to act as a
reflection grating. Suppose sunlight shines straight onto a beetle wing. If the melanin lines on the wing
are spaced 2.8 μm apart, what is the first-order diffraction angle for green light (λ = 550 nm)?
3.3 (p30.62)
A 1.5 V flashlight battery is connected to a wire with a resistance of 3.00 Ω. The figure shows the
battery's potential difference as a function of time. (a) What is the total charge lifted by the charge
escalator?
3.4
A 90μF capacitor that had been charged to 30V is discharged through a resistor. The figure shows the
capacitor voltage as a function of time. What is the value of the resistance?
3.5
The heart produces a weak magnetic field that can be used to diagnose certain heart problems. It is a
dipole field produced by a current loop in the outer layers of the heart.
(a) It is estimated that the field at the center of the heart is 100 pT. What current must circulate around an
8.0-cm-diameter loop, about the size of a human heart, to produce this field?
(b) What is the magnitude of the heart's magnetic dipole moment?
Measure 4:
Understand major issues and problems facing modern science and
technology, including issues related to ethics, cultural values, public policies,
and the impact of human activity upon the planet.
4.1
On average, each person in the industrialized world is responsible for the emission of 10,000 kg of carbon
dioxide CO2 every year. This includes CO2 that you generate directly, by burning fossil fuels to operate
your car or your furnace, as well as CO2 generated on your behalf by electric generating stations and
manufacturing plants. CO2 is a greenhouse gas that contributes to global warming. If you were to store
your yearly CO2 emissions in a cube at STP, how long would each edge of the cube be?
4.2
A typical nuclear reactor generates 1000MW (1000 MJ/s) of electrical energy. In doing so, it produces
2000MW of "waste heat" that must be removed from the reactor to keep it from melting down. Many
reactors are sited next to large bodies of water so that they can use the water for cooling. Consider a
reactor where the intake water is at 18 ºC. State regulations limit the temperature of the output water to
30ºC so as not to harm aquatic organisms. How many liters of cooling water have to be pumped through
the reactor each minute?
4.3
A refrigerator has a P compressor, but the compressor runs only N % of the time. (a) If electricity costs
pr, what is the monthly (30 day) cost of running the refrigerator? (b) A more energy-efficient refrigerator
with an P_eff compressor costs...
Measure 5:
Demonstrate knowledge in one area of science, including understanding its
basic principles, laws, and theories.
5.1
A spherically symmetric charge distribution produces the electric field E = (4900 r2) er N/C, where r is in
m.
a) What is the electric field strength at r = 25.0 cm?
b) What is the electric flux through a 38.0-cm-diameter spherical surface that is concentric with the
charge distribution?
c) How much charge is inside this 38.0-cm-diameter spherical surface?
5.2
The electric potential at the dot in the figure is 3320 V. What is charge q?
5.3
Two 5.0 × 5.0 cm metal electrodes are spaced 1.2 mm apart and connected by wires to the terminals of a
9.0 V battery.
(a) What is the charge on each electrode?
(b) What is the potential difference between electrodes?
(c) The wires are disconnected, and insulated handles are used to pull the plates apart to a new spacing of
2.4mm. What is the charge on each electrode?
(d) What is the potential difference between electrodes?
5.4
What power is dissipated by the 2Ω resistor in the figure?
PHYS 1610 – Engineering Physics II
Spring 2013
Instructor: J
Number of Students: 162
Mode of Assessment: Assignment (MasteringPhysics)
Measures
1
2
3
4
5
Problems
1.1
1.2
1.3
1.4
2.1
2.2
2.3
2.4
3.1
3.2
3.3
3.4
4.1
4.2
4.3
5.1
5.2
5.3
5.5
Average
Average
Competency Level
%
Complete
77.3
92.2
90.9
81.8
90.9
85.1
77.9
75.3
77.3
73.4
75.3
80.5
85.1
77.3
83.1
80.5
82.5
83.8
79.2
81.5
%
Average Score
99.2
92.6
95.0
93.7
91.4
93.5
95.8
94.8
99.2
94.7
94.8
97.6
100
96.6
99.2
96.0
94.0
90.7
95.9
95.5
Intermediate Ability
% National
Score
96.27
91.78
95.00
81.52
80.69
99.58
95.85
94.13
94.10
90.61
92.23
95.00
90.20
93.75
91.23
87.45
85.50
92.57
92.70
91.59
PROBLEMS:
Measure 1:
Articulate the philosophical and historical foundations of modern science.
1.1
Problem 22.6
Light from a sodium lamp (λ = 589 nm) illuminates two narrow slits. The fringe spacing on a screen
150cm behind the slits is 4.0 mm. What is the spacing (in mm) between the two slits?
1.2
Problem 26.3
a) What is the strength of the electric field at the position indicated by the dot in the figure?
b) What is the direction of the electric field at the position indicated by the dot in the figure? (Assume
that x-axis is horizontal and points to the right.)
1.3
Problem 26.16
A 16 cm × 16 cm horizontal metal electrode is uniformly charged to +48 nC. What is the electric field
strength 2.0 mm above the center of the electrode?
1.4
Problem 27.58
A sphere of radius R has total charge Q. The volume charge density (C/m3) within the sphere is
This charge density decreases linearly from ρ0 at the center to zero at the edge of the sphere.
a) Show that:
b) Show that the electric field inside the sphere points radially outward with magnitude
c) Show that your result of part (b) has the expected value at r = R.
Measure 2:
Understand the scientific method and demonstrate an ability to apply it across a
variety of situations.
2.1
Problem 26.37
The figure is a cross section of two infinite lines of charge that extend out of the page. The linear charge
densities are ± λ. Find an expression for the electric field strength E at height y above the midpoint
between the lines.
2.2
Problem 27.46
A uniformly charged ball of radius a and charge –Q is at the center of a hollow metal shell with inner
radius b and outer radius c. The hollow sphere has net charge +5Q.
a) Determine the electric field strength in the region r ≤ a.
b) Determine the electric field strength in the region a < r < b .
c) Determine the electric field strength in the region b ≤ r ≤ c.
2.3
Problem 33.26
At t = 0 s, the current in the circuit in the figure is I0. At what time is the current ½I0?
2.4
Problem 34.44
Assume that a 7.0-cm-diameter, 120 W light bulb radiates all its energy as a single wavelength of visible
light.
a) Estimate the electric field strength at the surface of the bulb.
b) Estimate the magnetic field strength at the surface of the bulb.
Measure 3:
Demonstrate an ability to conduct, and interpret the results of experiments aimed at
better understanding natural phenomena.
3.1
Problem 22.48
Light from a sodium lamp (λ = 589nm) illuminates a narrow slit and is observed on a screen 88.0 cm
behind the slit. The distance between the first and third dark fringes is 2.70 mm .
What is the width (in mm) of the slit?
3.2
Problem 30.41
The following figure shows a 4.0-cm-wide plastic film being wrapped onto a 2.0-cm-diameter roller that
turns at 90 rpm . The plastic has a uniform surface charge density of -2.1 nC/m2 .
a) What is the current of the moving film?
b) How long does it take the roller to accumulate a charge of -10 µC?
3.3
Problem 32.71
In the following figure, a long, straight, current-carrying wire of linear mass density µ is suspended by
threads. A magnetic field perpendicular to the wire exerts a horizontal force that deflects the wire to an
equilibrium angle θ.
a) Find an expression for the strength and direction of the magnetic field B.
b) What B deflects a 60 g/m wire to a 15° angle when the current is 10 A?
c) What is the direction of B?
3.4
Problem 33.30
A 100-turn, 2.0-cm-diameter coil is at rest in a horizontal plane. A uniform magnetic field 60° away from
vertical increases from 0.50 T to 2.5 T in 0.50 s.
What is the induced emf in the coil?
Measure 4:
Understand major issues and problems facing modern science and technology,
including issues related to ethics, cultural values, public policies, and the impact of
human activity upon the planet.
4.1
Problem 17.46
Your 300 ml cup of coffee is too hot to drink when served at 86.0°C. What is the mass of an ice cube,
taken from a -17.0°C freezer, that will cool your coffee to a pleasant 57.0°?
4.2
Problem 19.47
A typical coal-fired power plant burns 350 metric tons of coal every hour to generate 750MW of
electricity. 1 metric ton = 1000 kg. The density of coal is 1500 kg/m3 and its heat of combustion is
28MJ/kg. Assume that all heat is transferred from the fuel to the boiler and that all the work done in
spinning the turbine is transformed into electrical energy.
a) Suppose the coal is piled up in a 9.00m × 11.0m room. How tall must the pile be to operate the plant
for one day?
b) What is the power plant's thermal efficiency?
4.3
Problem 32.53
The heart produces a weak magnetic field that can be used to diagnose certain heart problems. It is a
dipole field produced by a current loop in the outer layers of the heart.
a) It is estimated that the field at the center of the heart is 100 pT. What current must circulate around an
8.0-cm-diameter loop, about the size of a human heart, to produce this field?
b) What is the magnitude of the heart's magnetic dipole moment?
Measure 5:
Demonstrate knowledge in one area of science, including understanding its basic
principles, laws, and theories.
5.1
Problem 17.62
Two cylinders each contain 0.20 mol of a diatomic gas at 350 K and a pressure of 3.0 atm. Cylinder A
expands isothermally and cylinder B expands adiabatically until the pressure of each is 1.0 atm.
a) What is the final temperature of the gas in the cylinder A?
b) What are the final temperature of the gas in the cylinder B?
c) What is the final volume of the gas in the cylinder A?
d) What is the final volume of the gas in the cylinder B?
5.2
Problem 28.35
A -3.6 nC charge is on the x-axis at x1= -7 cm and a 4.4nC charge is on the x-axis at x2 = 13 cm.
At what point or points on the y-axis is the electric potential zero?
5.3
Problem 29.36
An infinitely long cylinder of radius R has linear charge density λ. The potential on the surface of the
cylinder is V0, and the electric field outside the cylinder is:
5.4
Problem 32.66
A Hall-effect probe to measure magnetic field strengths needs to be calibrated in a known magnetic field.
Although it is not easy to do, magnetic fields can be precisely measured by measuring the cyclotron
frequency of protons. A testing laboratory adjusts a magnetic field until the proton's cyclotron frequency
is 10.5 MHz. At this field strength, the Hall voltage on the probe is 0.541 mV when the current through
the probe is 0.159 mA. Later, when an unknown magnetic field is measured, the Hall voltage at the same
current is 1.736 mV. What is the strength of this magnetic field?
PHYS 1617
HONORS PHYSICS II
PHYS 1617 – Honors Physics II
Spring 2013
Instructor: M
Number of Students: 24
Mode of Assessment: Exam
Measures
1
1
1
2
2
2
2
3
3
3
3
3
4
4
4
4
5
5
5
5
5
Problems
1.1
1.2
1.3
2.1
2.2
2.3
2.4
3.1
3.2
3.3
3.4
3.5
4.1
4.2
4.3
4.4
5.1
5.2
5.3
5.4
5.5
% Average Score
71
38
58
71
71
83
50
96
88
83
71
13
83
83
92
83
67
71
63
67
92
Average
71
Average Competency Level
Intermediate Ability
PROBLEMS:
1.
Articulate the philosophical and historical foundations of modern science
1.1
An unmagnetized metal sphere hangs by a thread. When the north pole of a bar
magnet is brought near, the sphere is strongly attracted to the magnet. Then the
magnet is reversed and its south pole is brought near the sphere. How does the
sphere respond?
a. It is strongly attracted to the magnet.
b. It is weakly attracted to the magnet.
c. It does not respond.
d. It is weakly repelled by the magnet.
e. It is strongly repelled by the magnet.
1.2
An electron in the beam of a TV picture tube is accelerated by a potential
difference of 2.00 kV. Then it passes through a region of transverse magnetic
field, where it moves in a circular arc with radius 0.180 m. What is the magnitude
of the field?
a. 1.20 x 10-5 T
b. 2.65 x 10-5 T
c. 2.65 x 10-4 T
d. 8.34 x 10-4 T
e. 9.24 x 10-4 T
1.3
Lightofwavelength500nminairentersaglassblockwithindexof
refraction,n=1.5.Whenthelightenterstheblock,whichofthefollowing
propertiesofthelightwillnotchange?
a. Thespeedofthelight
b. Thefrequencyoflight
c. Thewavelengthofthelight
2.
Understand the scientific method and demonstrate an ability to apply it
across a variety of situations.
2.1
An ice-cube tray of negligible mass contains 0.350 kg of water at 18.0C. How
much heat must be removed to cool the water to 0.00C and freeze it?
a. 34.2 kJ
b. 90.5 kJ
c. 104 kJ
d. 130 kJ
e. 143 kJ
2.2
In a gas at STP, what is the length of the side of a cube that contains a number of
molecules equal to the population of the earth (about 6 billion people)?
a. 0.61 m
b. 2.6 m
c. 3.9 m
d. 6.1 m
e. 22.4 m
2.3
A gas undergoes two processes. In the first, the volume remains constant at 0.200
m3 and the pressure increases from 2.00 x 105 Pa to 5.00 x 105 Pa. The second
process is a compression to a volume of 0.120 m3 at a constant pressure of 5.00 x
105 Pa. Find the total work done by the gas during both processes.
a. – 40 kJ
b. – 16 kJ
c. 0.0 kJ
d. 16 kJ
e. 40 kJ
2.4
Anobjectis50cmfromadiverginglenswithafocallengthof‐20cm.How
farfromthelensistheimage,andwhichsideofthelensisiton?
a. 14cm,onthesamesideastheobject
b. 14cm,ontheoppositesidefromtheobject
c. 30cm,onthesamesideastheobject
d. 33cm,onthesamesideastheobject
e. 33cm,ontheoppositesidefromtheobject
Demonstrate an ability to conduct, and interpret the results of experiments
aimed at better understanding natural phenomena.
3.
The next three questions all use the same set up below:
A 75-kg person holds out his arms so that his hands are 1.7 m apart. Typically, a
person’s hand makes up about 1.0% of his or her body weight. For round
numbers, we shall assume that all the weight of each hand is due to the calcium in
the bones, and we shall treat the hands as point charges. One mole of Ca contains
40.18 g and each atom has 20 protons and 20 electrons. Suppose that only 1.0%
of the positive charges in each hand were unbalanced by negative charge.
3.1
How many Ca atoms does each hand contain?
a. 1.12 x 1025 atoms
b. 2.31 x 1025 atoms
c. 6.02 x 1025 atoms
d. 7.82 x 1025 atoms
e. 9.13 x 1025 atoms
3.2
How many coulombs of unbalanced charge does each hand contain?
a. 1.1 x 105 C
b. 1.8 x 105 C
c. 3.6 x 105 C
d. 4.0 x 105 C
e. 9.6 x 105 C
3.3
What force would the person’s arms have to exert on his hands to prevent them
from flying off?
a. 1.0 x 1020 N
b. 4.0 x 1020 N
c. 5.0 x 1020 N
d. 1.6 x 1021 N
e. 2.9 x 1021 N
3.4
Whatdiametermustacopperwirehaveifitsresistanceistobethesameas
thatofanequallengthofaluminumwirewithdiameter3.26mm?(al=2.63
x10‐8m,c=1.72x10‐8m)
a. 2.14mm
b. 2.64mm
c. 3.26mm
d. 4.03mm
e. 6.93mm
3.5
Astereoamplifiercreatesa5.0Vpotentialdifferenceacrossaspeaker.To
doublethepoweroutputofthespeaker,theamplifier’spotentialdifference
mustbeincreasedto
a. 7.1V
b. 10V
c. 14V
d. 25V
e. 31V
4.
Understand major issues and problems facing modern science and
technology, including issues related to ethics, cultural values, public policies,
and the impact of human activity upon the planet.
4.1
If the air temperature is the same as the temperature of your skin (~ 30C) your
body cannot get rid of heat by transferring it to the air. In that case, it gets rid of
the heat by evaporating water (sweat). During bicycling, a typical 70-kg person’s
body produces energy at a rate of about 500 W due to metabolism, 80% of which
is converted to heat. How many kilograms of water must the person’s boy
evaporate in an hour to get rid of this heat? The heat of vaporization of water at
body temperature is 2.42 x 106 J/kg.
a.
b.
c.
d.
e.
0.01 kg
0.34 kg
0.60 kg
0.74 kg
4.32 kg
The next three questions all use the same set up below:
Electric Fields in an Atom. The nuclei of large atoms, such as uranium, with 92
protons, can be modeled as spherically symmetric spheres of charge. The radius
of the uranium nucleus is approximately 7.4 x 10-15 m.
4.2
Whatistheelectricfieldthisnucleusproducesjustoutsideitssurface?
a. 0N/C
b. 2.4x1021N/C
c. 3.1x1021N/C
d. 6.1x1021N/C
e. 1.2x1022N/C
4.3
Whatmagnitudeofelectricfielddoesitproduceatthedistanceofthe
electrons,whichisabout1.0x10‐10m?
a. 4.5x1012N/C
b. 1.3x1013N/C
c. 3.3x1013N/C
d. 7.2x1013N/C
e. 3.2x1015N/C
4.4
Theelectronscanbemodeledasformingauniformshellofnegativecharge.
Whatnetelectricfielddotheyproduceatthelocationofthenucleus?
a. 0N/C
b. 2.4x1021N/C
c. 3.1x1021N/C
d. 6.1x1021N/C
e. 1.2x1022N/C
5.
Demonstrate knowledge in one area of science, including understanding its
basic principles, laws, and theories.
5.1
How much work is needed to assemble an atomic nucleus containing three
protons (such as Be) if we model it as an equilateral triangle of side 2.00 x 10-15 m
with a proton at each vertex? Assume the protons started from very far away.
a. 0 J
b. 1.14 x 10-13 J
c. 2.31 x 10-13 J
d. 3.46 x 10-13 J
e. 4.60 x 10-13 J
5.2
At a certain distance from a point charge, the potential and electric field
magnitude due to that charge are 4.98 V and 12.0 V/m respectively. Take V = 0
at infinity. What is the magnitude of the charge?
a. 0.07 nC
b. 0.17 nC
c. 0.23 nC
d. 0.27 nC
e. 0.42 nC
The next three questions all use the same set up below:
A 5.00 pF, parallel-plate, air-filled capacitor with circular plates is to be used in a
circuit in which it will be subjected to potentials of up to 1.00 x 102 V. The
electric field between the plates is to be no greater than 1.00 x 104 N/C.
5.3
Whatshouldbetheradiusofeachplate?
a. 4.2mm
b. 5.7mm
c. 2.1cm
d. 4.2cm
e. 5.7cm
5.4
Whatshouldbethespacingofthecapacitor?
a. 1.0cm
b. 1.9cm
c. 2.2cm
d. 3.1cm
e. 5.0cm
5.5
Whatisthemaximumchargetheyshouldhold?
a. 63pC
b. 125pC
c. 250pC
d. 500pC