PHYSICS I UNIT 1 - science-b

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PHYSICS I
UNIT 1 Motion
Kinematics
One – Dimensional Motion
JAVA APPLETS
http://www.walter-fendt.de/ph14e/
WILEY APPLETS
http://higheredbcs.wiley.com/legacy/college/halliday/0
471320005/simulations6e/index.htm?newwindow=true
Lesson One
Motion chap 2
UNIT 1 Lesson 1
Objectives
Position vs. Time
Do Now!
Graphs
Men’s USA runner Maurice
 Using Data
Greene won the gold in the 100
meter sprint with a time of 9.87 s.  Calculate:
What was his average velocity?
Honor:
If his initial velocity was 0, what
was his average acceleration?
Homework




Problems
pg 52 #’s 43 – 50 ALL
Problems
pg 52 #’s 51 – 61 ODD
 Using


Average Velocities
Average Accelerations
UNIT 1 Lesson 1
Definition of Speed
Speed
is the distance traveled per
unit of time (a scalar quantity).
d = 20 m
A
Time t = 4 s
B
vs =
d
t
=
20 m
4s
vs = 5 m/s
Not direction dependent!
UNIT 1 Lesson 1
Definition of Velocity
Velocity
is the displacement per
unit of time. (A vector quantity.)
s = 20 m
Δx=12 m
A
20o
Time t = 4 s
B
= 3 m/s at 200 N of E
Direction required!
UNIT 1 Lesson 1
Lesson
#1
In Class
Equations of
one- dimensional
motion page 51
Answer Review
Concepts page 39
practice problems
#’s 9 – 13
PRACTICE / DEMO

Cart Rolling down Ramp
Measure Displacement
Measure Time
Calculate Average Velocity

Position vs. Time






http://webphysics.davidson.edu/physlet_resources/physlet_ph
ysics/contents/mechanics/one_d_kinematics/default.html
Constant Acceleration vs. Time
http://webphysics.davidson.edu/physlet_r
esources/physlet_physics/contents/mecha
nics/one_d_kinematics/default.html
The BIG 5
UNIT 1 Lesson 2
Chap 3
Objectives
Do Now!

Navy jets launch from aircraft
carriers using catapults go from
0 to launch speed in 175 feet
(5.334X 101 m) in 2.15 sec.
What is the average velocity as
it travels down the catapult?
How far has it traveled at 1.10
seconds?
Homework
Summary Sheet chap 3 terms,
 Solving for
-Average Velocity
-Acceleration, Final Velocity
 Page 61 & 64
 Practice Problems 1 – 10 ALL

Utilize THE BIG FIVE
EQUATIONS!!!
Equations on Page 79
(Chapter 3)
 Each student should be able
to solve for :
 Vf
when Vi, ,a and t are known
 Vi
when, Vf ,a and d are known
 d
when Vf , Vi and t are known
 d
when a , Vi and t are known
 a
when d , Vi , Vf and t are known
UNIT 1 Lesson 2
Vf2 = V02 + 2aΔd
E.g. A train accelerates from 10 m/s to 40 m/s at
an acceleration of 1m/s 2. what distance
does it cover during this time.
Using V2 = V02 + 2aΔs, we sub in values 40 for V,
10 for V0 and 1 for a. Re-arranging to solve for
s, we get:
ΔS = 750 m
With Significant Digits ΔS = 800 m
UNIT 1 Lesson 2
d = V0Δt + 0.5 a Δt2
E.g. A body starts from rest at a uniform acceleration
of 3 m/s2. how long does it take to cover a
distance of 100m.
Using d = V0Δt + 0.5 a Δt2, we sub in values 3 for a, 0
for V0 and 100 for s. Re-arranging the equation
and solving for t (using the quadratic formula), we
get:
t = 8.51 or -8.51 seconds. As time cannot be
negative, t = 8.51 seconds.
t = 9 seconds
UNIT 1 Lesson 2
d = Vavg * t = (V0 + Vf)/2 × t
A car decelerates from 20.0 m/s to 10.0 m/s
over a period of 10.0 seconds. How far
does it travel during this time period.
Using d = (V0 + Vf)/2 × t, we sub in values
20.0 for V0, 10.0 for Vf and 10.0 for t.
Solving for s, we get:
d = 150m
Note:
UNIT 1 Lesson 2
 All
units must be converted such that they are
uniform for different variable throughout the
calculations.
 Time  seconds
 Distance  meters
 Velocity  m/s
 Acceleration  m/s2
 Kinematic
quantities (except time) are
VECTORS and can be negative.
UNIT 1 Lesson 2
In Class
 Pages 60 – 63
 Examples 1 and 2
PRACTICE / DEMO
 Motion
with Constant
Acceleration

HOMEWORK
Summary Sheet chap 3 terms,
Solving for
-Average Velocity
-Acceleration, Final Velocity
Page 61 & 64
Practice Problems 1 – 10 ALL
REVIEW LAB I {F-150} Work Sheet
http://www.walterfendt.de/ph14e/acceleration.htm
Data Tables
and Graphs
UNIT 1 Lesson 3
Objectives
Calculate:
Average Velocities from data
tables (and graphs)

Do Now!
What is the average
acceleration of the
A-6 Intruder
as it travels down
the catapult from
0 to 150 Knots
(7.62 X 101 m/s)
in 2.15 seconds?
Calculate:
Average Accelerations from
data tables (and graphs)

Homework
 Pg:
65 - 71
 Practice Problems
 #19, 22, 25, 27 32
#41
UNIT 1 Lesson 3
Position vs. time graph (velocity)
9
8
p
o
s
i
t
i
o
n
No Motion (zero
velocity)
7
6
5
Uniform Motion
(constant
velocity)
4
3
Accelerated
Motion
(Increasing/chan
ging velocity)
2
1
0
x, (m)
1
2
3
time, t (s)
4
UNIT 1 Lesson 3
velocity vs. time graph (acceleration)
9
8
v
e
l
o
c
i
t
y
7
Uniform Motion (zero
Acceleation)
6
5
Uniform Acceleration
(constant
acceleration)
4
3
Decreasing
Acceleration
2
v,
1
(m/s)
0
1
2
3
time, t (s)
4
UNIT 1 Lesson 3
Graphical Analysis
vavg
Instantaneous Velocity:
Dx x2  x1


Dt t2  t1
x2
Dx
x1
Dt
t1
t2
vinst
Displacement, x
Average Velocity:
Dx

(Dt  0)
Dt
slope
Dx
Dt
Time
UNIT 1 Lesson 3
Uniform
Acceleration
in One Dimension:
 Motion
is along a straight line (horizontal,
vertical or slanted).
 Changes in motion result from a CONSTANT
force producing uniform acceleration.
 The velocity of an object is changing by a
constant amount in a given time interval.
 The moving object is treated as though it
were a point particle.
Example 6: An airplane flying initially at
400 ft/s lands on a carrier deck and stops in a
distance of 300 ft. What is the acceleration?
vo = 400 ft/s
vf = 0
+
Step 1. Draw and label sketch.
Step 2. Indicate + direction
Example: (Cont.)
vo = 400 ft/s
vf = 0
+
Step 3. List given; find information with signs.
Given: vo = 400 ft/s
v=0
- initial velocity of airplane
- final velocity after
traveling Δx = +300 ft
Find: a = ? - acceleration of airplane
Given: vo = +400 ft/s
v=0
Δx = +300 ft
Step 4. Select equation that
contains a and not t.
0
vf2 - vo2 = 2aΔx
a=
Why is the acceleration
negative?
-vo2
2x
=
-(400 ft/s)2
2(300 ft)
a = - 300 ft/s2
Because Force is in a negative direction
which means that the airplane slows down
Lesson #
Velocity LAB
UNIT 1 Lesson 4
Objectives
 Measuring

times of roll
Calculate


THE ACCELERATION
THE VELOCITIES
 OF
AN F-150 ROLLING
DOWN THE ACADEMIC
WING HILL.
Homework
 Complete
LAB 1
 BRING LAPTOP with “EXCEL”
for next class
UNIT 1 LESSON 5
Lab Review - Excel
Do Now!
By Team swap labs
Check Data and
Calculations
Read Results and
Conclusion sections
Objectives
 Utilizing
Excel
 Plot Data and obtain
Graphs of:



Evaluate Effort using
EEMO

..\..\Physics I
LABs\Motion\CarA
vs Car B Graphs and
data tables.xls
Position vs. Time
Velocity vs. time
Acceleration vs. time
Homework
On Excel create a graph that shows a
Lacrosse ball falling at a constant acceleration
of 9.8 m/s2 for 30 seconds.
Aaaaaaaah!
Free Fall
Do Now!
A lacrosse ball is dropped and
falls from the BIW Crane. If the
Cranes is 350.0 ft tall (107.7
meters).
How long will it take the ball to
hit the ground?
What will the velocity be?
Homework



Page 74 Practice
Problems #’s 42 – 46
Section Review
#’s 47
Page 82 #’s 97, 100, 101
UNIT 1 Lesson 6
Objectives
 Be
able to utilize
the BIG 5 Equations
to calculate:


Velocity
Displacement
of a falling
{NO Friction}
object on Earth
Sign Convention:
A Ball Thrown
Vertically Upward
avy==
=-0
+
avy=
==-++
ya
=+-v ==
• Displacement is positive
(+) or negative (-) based
on LOCATION.
UP = +
Release Point
vya==
=-0-
•
yv=
= -Negative
Negative
a=-
Velocity is positive (+)
or negative (-) based
on direction of motion.
• Acceleration is (+) or (-)
based on direction of
force (weight).
UNIT 1 Lesson 6
PRACTICE / DEMO
In Class
 Page
74 Practice
Problems #’s 42 – 46
 Section Review
#’s 47
 Page 82 #’s 97, 100,
101
 Free

Fall
http://higheredbcs.wiley.com/legacy/
college/halliday/0471320005/simulatio
ns6e/index.htm?newwindow=true
 Free Fall- 2
 http://www.walterfendt.de/ph14e/accelera
tion.htm
LAB 2
Calculate
Gravitational - Acceleration
in BATH, ME
UNIT 1 Lesson 7
Objectives
 Be
able to utilize
the BIG 5 Equations
to calculate:



Velocity
Displacement
Acceleration
of a moving object
Do Now! 2 minutes
A lacrosse ball is dropped and falls from
the BIW Crane. If the Cranes is 350.0 ft
tall (107.7 meters).
How long will it take the ball to hit the
ground?
What will the velocity be?
Homework
 Finish
LAB REPORT Typed
UNIT 1 Lesson 8









You must know how to do
these actions:
Calculate Average
Velocities from data
Calculate Average
Accelerations from data
Calculate times and
distances given Average
Velocities & Accelerations
Calculate Average
Velocities & Accelerations
given times and distances
Calculate and / or
measure Average
Velocities from data tables
(and graphs)
Calculate and / or
measure Average
Accelerations from data
tables (and graphs)
Calculate Acceleration
due to gravity of an object
in free fall
Calculate an objects
velocity in free fall
Constant
Acceleration
Motion
DO NOW:
What is the gravitational
Acceleration in Bath, ME?
Would it be larger or smaller on
Mount Everest? Why?
UNIT 1 Lesson 8
 In
Class /
Homework:
 Page 82 – 83
 #’s 103, 107, 108,
109, 110, 111, 11,
113
REVIEW
Test Lesson 10
LESSON 9 Review
PHYSICS I
UNIT 1 MOTION
Do NOW:
TEST
Homework:
Chapter 4
What are Newton’s
THREE Law’s
Give and example when it
they happened to YOU!
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