Name ______________________________ Period _____
Physics Fall Final Exam Review
Math in Physics
Find the length of the missing side and the measures of the two missing angles in the triangle below:
b = 6.24, angle 1 = 32, angle 2 = 58
MOTION GRAPHS
position (m)
Between which two points is:
A. the velocity constant and positive
__b-c____
B. the velocity equal to zero
__d-e____
C. the velocity increasing
__a-b___
D. the velocity decreasing
__c-d___
D
E
C
B
A
t (s)
Refer to the graph to answer each of the following:
A. How far does the object travel between
t = 0 and t = 40 sec?
___400 m____
B. How far does it travel between
t = 40 and t = 70 sec?
___0 m____
C. What is its velocity for the first 40 seconds? ___10 m/s____
D. What is the velocity between 40 and 70 s? ___0 m____
E. What is the velocity between 70 and 100 s? ___- 13.33 m/s____
F. What did the object do at t=70 seconds? Returniing to starting
point
The graph below shows the motion of a car accelerating from a stop at an intersection.
1. How fast was the car moving at the following times?
a) 2.0 s
b) 4.0 s
c) 15.0 s
10 m/s
30 m/s
80 m/s
2. Determine the acceleration during the following intervals:
a) 0 to 5.0 s
b) 5.0 to 10.0 s
c) 10.0 s to 15.0 s
8 m/s
4 m/s/s
4 m/s/s
Name ______________________________ Period _____
SPEED AND ACCELERATION
1. The velocity of a car increases from 2.0 m/s at 1.0 s to 16 m/s at 4.5 s. What is the car’s average
acceleration?
4 m/s/s
2. Starting from rest, your new truck accelerates at the rate of 5 m/s2 for 12 s. What will be its speed at the
end of the 12 s?
60 m/s
3. A train leaves the station traveling west. If its average speed is 7.5 m/s, how long will it take to go 450 km?
60,000 s
VECTORS
A measurement which has magnitude only is called a
_____Scalar___________
A measurement which has magnitude and direction is a _____Vector________________
What is the difference between speed and velocity? ___speed = Scalar, velocity = vector
Given:
A = 8 units, W
B = 3 units, N
C = 5 units, E
Use the graph to add the following vectors. Draw and label the resultant.
A+B
R = 8.54 @ 20.55
A+C
R = 3 units west
KINEMATIC EQUATIONS
1. An airplane accelerates down a runway at 3.20 m/s2 for 32.8 s until is finally lifts off the ground.
Determine the distance traveled before takeoff.
179,127.36 m
2. A bike accelerates uniformly from rest to a speed of 7.10 m/s over a distance of 35.4 m.
Determine the acceleration of the bike.
.71 m/s/s
Name ______________________________ Period _____
3. A car traveling at 22.4 m/s skids to a stop in 2.55 s. Determine the skidding distance of the car.
28.56 m
4. A baseball is popped straight up into the air and reaches its maximum height in 3.13 seconds.
How high does the ball go?
48.05 m
PROJECTILE MOTION
1. Divers at Acapulco dive from a cliff that is 60 m high. If the rocks below the cliff extend outward for 20 m,
what is the minimum horizontal velocity a diver must have to clear the rocks safely? 5.71 m/s
2. A discus is thrown form the top of a 100m high building with a velocity of 12 m/s. Find:
a. Initial Horizontal and vertical velocities
Vx = 12 m/s, Vy = 0 m/s
b. When does the discus hit the ground?
4.52 s
c. What is its total horizontal range?
54.18 m
3. In her physics lab, Melanie rolls a 10 g marble down a ramp and off the table with a horizontal velocity of
1.2 m/s. The marble falls in a cup placed 0.51 m from the table. How high is the table? (0.92 m)
4. Emanuel Zacchini, the famous human cannonball, was fired out of a cannon with a speed of 24.0 m/s from
a height of 56.6 m, how long was Zacchini in the air? (3.4 s)
NEWTON’S LAWS OF MOTION AND FORCES
1. What is the weight of a 70 kg object? ______686.7 N______________
2. What is the acceleration of a 70 kg object that is being pushed with a force of 4900 N? ____70 m/s_______
3. When acceleration is constant, velocity is ______Not Constant – or changing velocity___________.
Name ______________________________ Period _____
4. Two forces, one of 85 N and the other of 32 N, act in opposite directions as shown. What is the acceleration
of the box if its mass is 25 kg?
-2.12 m/s/s
85 N
32 N
5. What is the tendency of an object to maintain its state of motion?
32 N
____Inertia________
6. What does Newton's 3rd Law say? ____Every action force has an equal and opposite reaction force.______
7. Fill in the blanks on this force diagram:
Fn = 100 N
M = 10.19 kg
a = .98 m/s/s
Fnet = 10 N
m = .1
8. A 2 Kg bowling ball is suspended motionless by a cord attached to a 100 ft high ceiling.
a) What is the weight of the bowling ball? 19.62 N
b) What is the magnitude and direction of the force exerted by the cord on the ball? 19.62 N
c) What is the net force on the ball? 0 N
d) What is the acceleration of the ball? 0 N
e) Assume the cord is cut. What is the acceleration of the ball after the cord is cut? -9.81 m/s/s
f) What is the net force on the ball after the cord is cut? -19.62 N
9. A force of 3 N is exerted on a box which slides on a frictionless table. If the acceleration of the box is 2
m/s2, what is the mass of the box? 1.5 kg
10. What does Newton's 2nd Law say? _____F = ma_______________________________________________
Name ______________________________ Period _____
11. A box with a weight of 24 N rests on a horizontal surface where the coefficient of friction is 0.12. A force of 42
N is applied horizontally on the box.
a) What is the net force on the box? 21.12 N
b) What is the acceleration of the box? 8.62 m/s/s
12. A horizontal force pulls a cart with a mass of 55 kg with constant velocity across a floor where the coefficient of
friction is 0.25. What is that force? 134.89N
13. What does inertia depend on? ___mass____________
14. Student A lifts a 50.0-newton box from the floor to a height of 0.40 meter in 2.0 seconds. Student B lifts a 40.0newton box from the floor to a height of 0.50 meter in 1.0 second. Compared to student A, student B does
(1) the same work but develops more power
(2) the same work but develops less power
(3) more work but develops less power
(4) less work but develops more power
15. While riding a chairlift, a 55-kilogram skier is raised a vertical distance of 370 meters. What is
the total change in the skier’s gravitational potential energy? 199,633.5J
16. Which object has the greatest inertia?
(1) a 5.00-kg mass moving at 10.0 m/s
(2) a 10.0-kg mass moving at 1.00 m/s
(3) a 15.0-kg mass moving at 10.0 m/s
(4) a 20.0-kg mass moving at 1.00 m/s
17. Two spheres, A and B, are simultaneously projected horizontally from the top of a tower.
Sphere A has a horizontal speed of 40.0 meters per second and sphere B has a horizontal speed
of 20.0 meters per second. Which statement best describes the time required for the spheres to
reach the ground and the horizontal distance they travel?
(1) Both spheres hit the ground at the same time and at the same distance from the base
of the tower.
(2) Both spheres hit the ground at the same time, but sphere A lands twice as far as
sphere B from the base of the tower.
(3) Both spheres hit the ground at the same time, but sphere B lands twice as far as
sphere A from the base of the tower.
(4) Sphere A hits the ground before sphere B, and sphere A lands twice as far as sphere B
from the base of the tower.
18. A student pulls a 60.0-newton sled with a force having a magnitude of 20. newtons. What is the
magnitude of the force that the sled exerts on the student?
(1) 20.0 N
(3) 60.0 N
(2) 40.0 N
(4) 80.0 N
Name ______________________________ Period _____
Work, Power & Energy
19.
a.
b.
c.
A force does work on an object if a component of the force
is perpendicular to the displacement of the object.
is parallel to the displacement of the object.
perpendicular to the displacement of the object moves the object along a path that returns
the object to its starting position.
d. parallel to the displacement of the object moves the object along a path that returns the
object to its starting position.
20.
a.
b.
c.
d.
The more powerful the motor is,
the longer the time interval for doing the work is.
the shorter the time interval for doing the work is.
the greater the ability to do the work is.
the shorter the workload is.
21. How much work is done in pulling an 80 kg wagon 20 m with a force of 10 N?
200J
22. Answer the same question above assuming there is a friction force of 3N.
140J
23. What the gain in potential energy for a 65 kg women climbing a 200 m high tree?
24. How much work did she do?
127,530 J
127,530 J
25. If she climbed the tree in 15 seconds, what was here power output?
8,502 w
26. A construction worker pushes a wheelbarrow 5.0 m with a horizontal force of 50.0 N. How much work is
done by the worker on the wheelbarrow?
250 J
27. What do we cal the sum of kinetic energy and all forms of potential energy? _____Mechanical Energy ___
28. Describe how the conservation of energy applies to a pencil falling from a desk?
_____Pencil loses PE as it falls and gains KE. Total energy remains constant as it falls.
_____________________________________________________________________________
Name ______________________________ Period _____
29. A 3.00 kg toy falls from a height of 10.0 m. Just before hitting the ground, what will be its kinetic energy?
(Disregard air resistance. g = 9.81 m/s2.)
294.3 J
30. What is the kinetic energy of a 0.135 kg baseball thrown at 40.0 m/s?
108 J
31. How much energy does a 2500000 kg airplane have when it is flying at an altitude of 3000 m with a
velocity of 80 m/s?
81,575,000,000 J
32. The main difference between kinetic energy and potential energy is that
a. kinetic energy involves position and potential energy involves motion.
b. kinetic energy involves motion and potential energy involves position.
c. although both energies involve motion, only kinetic involves position.
d. although both energies involve position, only potential involves motion.
38. The largest watermelon ever grown had a mass of 118 kg. Suppose this watermelon were exhibited on a
platform 5.00 m above the ground. After the exhibition, the watermelon is allowed to slide along to the
ground along a smooth ramp. How high above the ground is the watermelon at the moment its kinetic
energy is 4.61 kJ?
1.02 m
39. Use energy conservation to fill in the blanks in the following diagram.
PE1 = .4J
KE 2.4J
KE = 0 J, PE 2.4 J
40. What is the velocity of the pendulum at point C? What is the height of the pendulum above at point B?
Can’t solve with out mass
Name ______________________________ Period _____
Momentum
41.
An object at rest may have
a) velocity
42. An object in motion need NOT have
a) velocity
43. An object that has momentum must also have
b) momentum
b) momentum
a) acceleration
b) impulse
c) KE
d) PE
c) KE
d) PE
c) KE
d) PE
44. A car weighs 7840 N. (a) What is its mass? (b) The car’s velocity is 25 m/sec eastward. What is its
momentum? (c) The car was accelerated from rest to 25 m/sec by a force of 1000 N. How long did the force
act to give it this velocity?
A. 799.18 kg
B. 19979.61 kg m/s
C. 19.98 s
45. A force of 6 N acts on a body for 10 sec. (a) What is the body’s change in momentum? (b) The mass of the
body is 3 kg. What is its change in speed?
a. 60 Ns
b. 20 m/s
46. A car weighing 15680 N and moving at 20 m/sec is acted upon by a 640-N force until it is brought to a halt.
(a) What is the car’s mass? (b) What is the initial momentum? (c) What change in the car’s momentum does
the force bring about? (d) How long does the braking force act on the car to bring it to a halt?
A. 1598.35 kg
B. 31,967.38 kg m/s
C. 31,967.38 kg m/s
D. 49.94 s
47. A 40-kg projectile leaves at 2000-kg launcher with a velocity of 800 m/sec forward. What is the recoil
velocity (speed and direction) of the launcher?
-16 m/s
48. A stationary Volkswagen Rabbit of mass 1,000 kg is rammed from behind by a 1965 Ford Mustang with a
mass of 1200 kg, traveling 20 m/s on an icy road. If they lock bumpers in the collision, how fast will the
pair move forward? (11 m/s)
49. An arrow traveling at 40 m/s strikes and imbeds itself into a 400 g apple at rest. (You go, William Tell!) The
apple with the arrow in it moves off horizontally at 10 m/s after the impact. What is the mass of the arrow? (0.133
kg)
Name ______________________________ Period _____
50. In each of the following collisions, find the unknown:
Before
a)
v' = ___5.4 m/s_____
m1 = ___3.2 kg_____
2 kg
5 kg
2 kg
4 m/s
v'
6 m/s
m1
2 kg
5 kg
5 m/s
b)
After
m1
10 m/s
2 kg
6 m/s
5 m/s
2 m/s
51. A 0.5 kg mass moving East with a velocity of 8 m/s is acted upon by a force of 20 N for 2.0 sec.
a) What is the initial momentum of the mass? 4 kg m/s
b) What impulse was given to the mass?
40 Ns
c) What is the final momentum of the mass?
44 kg m/s
d) What is the final velocity of the mass?
88 m/s