Assessment Chapter Test A - Miss Cochi's Mathematics

Name:______________________________Class:__________________ Date:__________________

Assessment

Chapter Test A

Teacher Notes and Answers

Forces and the Laws of Motion

CHAPTER TEST A (GENERAL)

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

21.

22.

23.

c

d

d

c

c

c

c

b

d

d

c

a

d

d

b

d

c

d

Forces exerted by the object do not change

its motion.

An object at rest remains at rest and an

object in motion continues in motion with

constant velocity unless it experiences a net

external force.


F is the vector sum of the external forces

acting on the object.

In most cases, air resistance increases with

increasing speed.

27 N, to the right

Given

F1 = 102 N, to the right

24. 16 N

Given

m = 33 kg

a = 0.50 m/s2

Solution

Fnet, x =
Fx = max =

(32 kg)(0.50 m/s2 ) = 16 N

25. 10.4 N

Given

m = 1.10 kg


= 15.0¡ã

g = 9.81 m/s2

Solution

Fnet, y =
Fy = Fn  Fy = 0

 = 180¡ã  90¡ã  15.0¡ã = 75.0¡ã

Fn = Fy = Fg sin  = mg sin 

Fn = (1.10 kg)(9.81 m/s2 )(sin 75.0¡ã)

= 10.4 N

F2 = 75 N, to the left

Solution

Fnet = F1 + F2

Fnet = F1
F2 = 102 N
75 N = 27 N

Fnet = 27 N, to the right

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Chapter Tests

Name:______________________________Class:__________________ Date:__________________

Assessment

Forces and the Laws of Motion

Chapter Test A

MULTIPLE CHOICE

In the space provided, write the letter of the term or phrase that best completes

each statement or best answers each question.

_____ 1. Which of the following is the cause of an acceleration?

a. speed

c. force

b. inertia

d. velocity

_____ 2. What causes a moving object to change direction?

a. acceleration

c. inertia

b. velocity

d. force

_____ 3. Which of the following forces exists between objects even in the

absence of direct physical contact?

a. frictional force

c. contact force

b. fundamental force

d. field force

_____ 4. A newton is equivalent to which of the following quantities?

a. kg

c. kg?m/s2

b. kg?m/s

d. kg?(m/s)2

_____ 5. The length of a force vector represents the

a. cause of the force.

b. direction of the force.

c. magnitude of the force.

d. type of force.

_____ 6. A free-body diagram represents all of the following except

a. the object.

b. forces as vectors.

c. forces exerted by the object.

d. forces exerted on the object.

_____ 7. In the free-body diagram shown to the right,

which of the following is the gravitational force

acting on the car?

a. 5800 N

c. 14 700 N

b. 775 N

d. 13 690 N

Original content Copyright ? by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.

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Chapter Tests

Name:______________________________Class:__________________ Date:__________________

Chapter Test A continued

_____ 8. Which of the following is the tendency of an object to maintain its state

of motion?

a. acceleration

c. force

b. inertia

d. velocity

_____ 9. A crate is released on a frictionless plank inclined at angle
with

respect to the horizontal. Which of the following relationships is true?

(Assume that the x-axis is parallel to the surface of the incline.)

a. Fy = Fg

c. Fy = Fx

d. none of the above

b. Fx = 0

_____ 10. A car goes forward along a level road at constant velocity. The

additional force needed to bring the car into equilibrium is

a. greater than the normal force times the coefficient of static friction.

b. equal to the normal force times the coefficient of static friction.

c. the normal force times the coefficient of kinetic friction.

d. zero.

_____ 11. If a nonzero net force is acting on an object, then the object is definitely

a. at rest.

c. being accelerated.

b. moving with a constant velocity. d. losing mass.

_____ 12. Which statement about the acceleration of an object is correct?

a. The acceleration of an object is directly proportional to the net

external force acting on the object and inversely proportional to the

mass of the object.

b. The acceleration of an object is directly proportional to the net

external force acting on the object and directly proportional to the

mass of the object.

c. The acceleration of an object is inversely proportional to the net

external force acting on the object and inversely proportional to the

mass of the object.

d. The acceleration of an object is inversely proportional to the net

external force acting on the object and directly proportional to the

mass of the object.

_____ 13. Which are simultaneous equal but opposite forces resulting from the

interaction of two objects?

a. net external forces

c. gravitational forces

b. field forces

d. action-reaction pairs

_____ 14. Newton¡¯s third law of motion involves the interactions of

a. one object and one force.

c. two objects and one force.

b. one object and two forces.

d. two objects and two forces.

Original content Copyright ? by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.

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Chapter Tests

Name:______________________________Class:__________________ Date:__________________

Chapter Test A continued

_____ 15. The magnitude of the gravitational force acting on an object is

a. frictional force.

c. inertia.

b. weight.

d. mass.

_____ 16. A measure of the quantity of matter is

a. density.

c. force.

b. weight.

d. mass.

_____ 17. A change in the gravitational force acting on an object will affect

the object¡¯s

a. mass.

c. weight.

b. coefficient of static friction.

d. inertia.

_____ 18. What are the units of the coefficient of friction?

a. N

c. N2

b. 1/N

d. The coefficient of friction has

no units.

SHORT ANSWER

19. In a free-body diagram of an object, why are forces exerted by the object not

included in the diagram?

_________________________________________________________________

_________________________________________________________________

20. State Newton¡¯s first law of motion.

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

21. In the equation form of Newton¡¯s second law,
F = ma, what does
F

represent?

_________________________________________________________________

_________________________________________________________________

22. What happens to air resistance when an object accelerates?

_________________________________________________________________

_________________________________________________________________

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Chapter Tests

Name:______________________________Class:__________________ Date:__________________

Chapter Test A continued

PROBLEM

23. In a game of tug-of-war, a rope is pulled by a force of 75 N to the left and by a

force of 102 N to the right. What is the magnitude and direction of the net

horizontal force on the rope?

24. A wagon having a mass of 32 kg is accelerated across a level road at

0.50 m/s2. What net force acts on the wagon horizontally?

25. Basking in the sun, a 1.10
kg lizard lies on a flat rock tilted at an angle of

15.0¡ã with respect to the horizontal. What is the magnitude of the normal force

exerted by the rock on the lizard?

Original content Copyright ? by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.

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Chapter Tests

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