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Unit 2a Force and Motion Study Guide
1. Label the following with the proper SI unit from these unit label choices :
km/h, mph, f/s, m/s, m/h, m/s2, g, kg, km, m, N, m/s North (or south, east or
west)
Acceleration___m/s2_
Velocity__m/s North
Mass___kg__ Distance__m____
Force__N_____
Speed__m/s__
2. True or False:
_True_______ You are traveling in a car at a constant speed of 50 km/hr and are
turning through a curve in the road to the right. You and the vehicle are
experiencing acceleration.
_True___ You experience acceleration when you have a change in direction.
_False__ A change in speed is not always a change in acceleration.
_False__ Your velocity changes from 50 m/s West to 50 m/s Southwest. You have
not experienced acceleration.
3. You are running on a moving walkway at 4 m/s east, which is the opposite direction
of the moving walkway. The walkway is moving at 5 m/s. Your resultant velocity is
a. 1 m/s west
b. 9 m/s east
c. 1 m/s east
d. 9 m/s west
4. A truck is traveling 27 m/s south and speeds up to 30 m/s. Check all that apply.
__x_ this is a change in speed
__x_ this is a change in velocity
__x_ this is a change in acceleration
5. Acceleration occurs when a __force___ is applied to an object and this acceleration
is in the _same____ direction as the applied __force___.
6. When a roller coaster makes a sharp turn, you slide in the opposite direction of the
turn because of __inertia___.
7. Newton’s first law of motion states that
a. an object in motion remains in motion unless acted upon by an unbalanced
force.
b. an object in motion eventually comes to a stop.
c. objects in motion accelerate in a vacuum
d. for every action, there is an equal and opposite reaction.
8. You are holding a 10 N medicine ball over your head.
a. the downward force on the ball is 10 N.
b. the upward force of your hands is 10 N.
c. the mass of the ball is 20 N.
d. this is an example of an unbalanced force.
e. both a and b.
9. Newton’s __third_____ law of motion states that if a force is exerted on an object,
another force occurs that is equal in size and opposite in direction.
10. Newton’s __first_____ law of motion states that an object in __motion___ tends to
stay in __motion______ and an object at __rest_____ tends to stay at _rest___
unless acted upon by an unbalanced force.
11. A small car and a large truck are moving at equal velocities. Which of the following
are true?
a. They are moving in the same direction.
b. The truck has greater inertia.
c. They are moving in opposite directions.
d. Both a and b.
12. _Inertia__ is the tendency of an object to resist any change in its motion.
13. Force pairs (circle all that apply)
a. act on the same object.
b. do not act on the same object.
c. are always equal.
d. are always unequal.
14. A bowling ball, a ping pong ball, a baseball and a tennis ball are released from the
top of the same ramp and onto a flat surface. Which ball will roll the farthest?
a. bowling ball
b. tennis ball
c. baseball
d. ping pong ball
15. Force is measured in
a. Newtons
b. Kg
c. m/s/s
d. kg/hr
16. ___Force__ is a push or a pull.
17. __Force___ can cause an object to change direction, stop or accelerate.
18. _Friction_ is a force that opposes motion between two surfaces that are touching.
19. True or False
__False___ Friction is in the same direction as an objects motion.
__True____ Friction increases with a larger mass.
__False___ Friction is eliminated with a lubricant.
20. The net force on a falling object is zero. Which is true?
a. Acceleration is zero.
b. The object falls at a constant velocity.
c. Both a and b.
d. None of the above.
21. The same object has
a. the same weight on the moon as on earth.
b. the same mass on the earth as the moon.
c. the same weight and mass on the moon and earth.
d. different mass and weight on the earth and the moon.
Show all work on the following questions
22. You have been running at 8 m/s for 1 minute. How far have you run?
Speed = Distance/Time
8 m/s = d/60 s
(8 m/s) x (60 s) = 480 m
23. You are in a race car and after 10 seconds you are travelling at 23 m/s from a dead
stop. What is your acceleration?
Acceleration = Final velocity – starting velocity / Time
a = 23 m/s – 0 m/s
10 s
a = 2.3 m/s2
24. You are on a moving walkway at Dulles airport which is moving east at 5 m/s. You
are walking east on the walkway at 2 m/s. What is your resultant velocity?
5 m/s east + 2 m/s east = 7 m/s east
25. What is the acceleration of a 100 kg mass if a force of 60 N acts on it? (F = m x a)
Force = Mass x Acceleration
60 N = 100 kg X a
60 n / 100 kg = .60 m/s2
26. A student is pushing on a box with a force of 8 N north. Another student is pushing
on the same box with a force of 9 N north. What is the net force?
8 N north + 9 N north = 17 N north