Name:__________________
IP 614
Block:____
Date:____/____/____
Forces Review
Force Identification
Forces to Choose From:
Gravity
Fg
Tension
Ft
Spring
Fs
Normal
Friction
Air Resistance
FN
Ff
Far
1. What two forces are exerted on the leaf while it falls?
_________________________ and _________________________.
2. What force does the rope exert on the people? __________________________
3. The weight of an object is a measure of the force of ____________________.
4. When you push a chair, what force (between the floor and the chair) opposes your
push? ___________________
A few basic facts about forces
Word Bank:
 Newton
 Balanced




Push
Unbalanced
Pull
Equilibrium
5. A force is a ___________________ or a __________________.
6. Forces are measured in units of ________________________.
7. ___________________ forces result in changes in motion.
8. ___________________ forces result in no changes in motion.
9. When forces are balanced, the object is said to be in ___________________.
Multiple Choice Review
_________ 10. All of the following are forces except
a. gravity. b. mass. c. magnetism.
d. friction.
_________ 11. The force that opposes the downward motion of a falling object falling through air is called
a. pressure. b. terminal velocity. c. air resistance. d. friction.
_________ 12. Hail falls to the ground because of the force of
a. magnetism. b. friction. c. gravity. d. electricity.
_________ 13. ___________________ Sand is sometimes spread on an icy surface in order to
a. decrease friction.
b. increase air resistance.
c. decrease air resistance. d. increase friction.
_________ 14. As you push a chair, friction equal to a force of 5 N pushes in the opposite
direction. How will the force needed to push the chair at a constant speed
compare to the force of friction?
a. The comparison depends on the type of friction.
b. The force will be less.
c. The force will be equal to the force of friction.
d. The force will be greater.
_________ 15. The weight of an object tells you
a. how large the object is.
b. how heavy the object is.
c. how tall the object is.
d. the shape of the object.
_________ 16. If an object is said to be in equilibrium, then the forces acting on the object must
be:
a. balanced
b. unbalanced
c. changing
d. zero
Free Body Diagrams/Other Questions
17. Draw and label a free-body diagram for the person riding a bike. Assume the person
is coasting to a stop. Include air resistance.
18. Draw and label a free-body diagram for football player #22 (Biff). Biff. Biff is tackled
and falls to the ground. Draw and label a FBD (free-body diagram) of Biff as he
slides along the ground (he is slowing down) after the fall. Ignore air resistance.
19. Draw and label a free-body diagram for a piece of paper that fell out of Tommy’s
suitcase. Include air resistance.
20. Name three forces that do not require contact.
21. Describe the motion of an object that has balanced forces acting on it.
22. Johnny is pushing a 42 N crate to the left with a force of 20N, Sally is pulling the
same crate to the right with a force of 17 N. Draw a free-body-diagram and calculate
the net force. Are the forces balanced or unbalanced?
23. Is force is a vector or scalar? Explain why.
24. Keoni is at football practice when it is time to push the sled. He notices that it takes
more force to start the sled moving than to keep it moving. Explain this phenomena
using the terms static friction, kinetic friction, and net force.
More Free-Body (Force) Diagrams.
For each of the following situations, identify the forces and the sources.
24. A star is popping out of a box. Identify the forces acting on the star.
1
2
Force
Source
1
2
25. A boy is pulling a sled. The sled is being dragged to the left. Identify the forces on
the sled. (The rope is pulling the sled to the left.)
1
2
4
3
Force
Source
Tension
Rope
1
2
3
4
MCAS Questions: Questions 1-8
_____ 26. The pull of gravity on Earth is a direct result of the
A. mass of Earth.
B. magnetic field of Earth.
C. rotation of Earth on its axis.
D. weight of Earth’s atmosphere.
_____ 27. On Earth, Johanna weighs 100 lbs. She calculated what her weight would be
at several other locations in the solar system. The results are shown in the
table below.
Location in
Weight
Solar System
(lbs.)
Venus
Earth
Moon
Mars
90
100
16
40
Jupiter
260
Which of the following statements is best supported by the information in the
table?
A. Venus has more gravitational force than Earth.
B. Mars has less gravitational force than the Moon.
C. Earth has four times the gravitational force of Mars.
D. Jupiter has more than twice the gravitational force of Earth.
_____ 28. The force of gravity on an object depends primarily on the object’s
A. density.
B. mass.
C. momentum.
D. volume.
_____ 29. Two forces act on the box shown below. A 4 N force acts to the right and a 6
N force acts to the left. What is the net force acting on the box?
6N
A.
B.
C.
D.
10 N to the right
10 N to the left
2 N to the right
2 N to the left
4N
_____ 30. The illustration below shows a 2-ton elephant balancing on a tree stump.
Which of the following statements must be accurate?
A.
B.
C.
D.
The weight of the tree stump is greater than 2 tons.
A 4-ton force on the ground spreads out in all directions.
The tree stump is exerting a 2-ton force upward on the elephant.
The downward force on the ground under the tree stump is 4 tons.
_____ 31. The forces acting on a skateboarder moving at a constant velocity along a
sidewalk are shown in the figure below.
Which of the following is the net force on the skateboarder?
A.
B.
C.
D.
0N
70 N
670 N
1270 N
_____ 32. A hot air balloon exerts a force
of 1200 N while lifting a load of
800 N. Which free-body force
diagram below depicts the
forces involved?
_____ 33. An upward force of 150 N is
applied to a box weighing 70 N.
Which of the following is the
free-body force diagram for this
situation?