PHYSICS: NEWTON’S LAWS AND FORCES
NUMBER __________
MULTIPLE CHOICE
1. Accelerations are produced by
a.
b.
c.
d.
e.
net forces.
velocities.
accelerations.
masses.
none of the above.
2. How does acceleration of an object change in relation to its mass? It is
a. directly proportional.
b. Acceleration doesn't depend on mass at all.
c. inversely proportional.
3. The acceleration produced by a net force on an object is
a. inversely proportional to the mass of the object.
b. directly proportional to the magnitude of the net force.
c. in the same direction as the net force.
d. all of the above.
e. none of the above.
4. Suppose the force of friction on a sliding object is 25 N. The force needed to maintain a constant velocity is
a. more than 25 N.
b. 25 N
c. less than 25 N.
5. A book weighs 4 N. When held at rest in your hands, the net force on the book is
a. 0 N.
b. 0.4 N.
c. 4 N.
d. 39 N.
e. none of the above
6. An apple weighs 1 N. The net force on the apple when it is in free fall is
a. 0 N.
b. 0.1 N.
c. 1 N.
d. 9.8 N.
e. none of the above
7. A net force of 3 N accelerates a mass of 3 kg at the rate of 1 m/s 2. The acceleration of a mass of 6 kg acted
upon by a net force of 6 N is
a. twice as much.
b. half as much.
c. the same.
d. none of the above
8. A push on a 1-kilogram brick accelerates the brick. Neglecting friction, to equally accelerate a 10-kilogram
brick, one would have to push
a. with 100 times as much force.
b. with 10 times as much force.
c. with just as much force.
1
d.
with
the amount of force.
10
e.
none of the above
9. A box is dragged without acceleration in a straight-line path across a level surface by a force of 13 N. What
is the frictional force between the box and the surface?
a. 13 N
b. Less than 13 N
c. More than 13 N
d. Need more information to say.
10. Suppose a particle is accelerated through space by a constant 10-N force. Suddenly the particle encounters
a second force of 10-N in a direction opposite to that of the first force. The particle
a. is brought to a rapid halt.
b. theoretically accelerates to speeds approaching the speed of light.
c. continues at the speed it had when it encountered the second force.
d. gradually decelerates to a halt.
e. none of the above
11. If the net force acting on a cart doubles, what happens to the cart's acceleration?
a. It quarters.
b. It halves.
c. It stays the same.
d. It doubles.
e. It quadruples.
12. Suppose a cart is being moved by a force. If suddenly a load is dumped into the cart so that the cart's mass
doubles, what happens to the cart's acceleration?
a. It quarters.
b. It halves.
c. It stays the same.
d. It doubles.
e. It quadruples.
13.
You pull horizontally on a 50-kg crate with a force of 450 N and the friction force on the crate is 250 N. The
acceleration of the crate is
a. 2 m/s2.
b. 4 m/s2.
c. 9 m/s2.
d. 14 m/s2.
14. A jumbo jet cruises at a constant velocity when the total thrust of the engines on the jet is 50,000 N. How
much air resistance acts on the jet?
a. 0 N
b. 25,000 N
c. 50,000 N
d. 75,000 N
e. 100,000 N
15.
The law of inertia states that an object
a. will continue moving at the same velocity unless an outside force acts on it.
b. will continue moving in a straight line unless an outside force acts on it.
c. that is not moving will never move unless a force acts on it.
d. at rest will remain at rest unless acted on by an outside force.
e. will do all of the above.
16.
The law of inertia applies to
a. objects at rest.
b. moving objects.
c. both moving and nonmoving objects.
17.
A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked
quickly. The reason this can be done is that
a. gravity pulls very hard on the milk carton.
b. the milk carton has very little weight.
c. the milk carton has inertia.
d. none of the above
18.
One object has twice as much mass as another object. The first object also has twice as much
a. velocity.
b. gravitational acceleration.
c. inertia.
d. all of the above
19.
Compared to its weight on Earth, a 10-kg object on the moon will weigh
a. the same amount.
b. less.
c. more.
20.
Compared to its mass on Earth, the mass of a 10-kg object on the moon is
a. the same.
b. more.
c. less.
21.
The mass of a sheep that weighs 110 N is about
a. 1 kg.
b. 11 kg.
c. 110 kg.
d. 1100 kg.
e. none of the above
22.
Friction
a. comes from microscopic bumps that act as obstructions to the object's motion.
b. is the name given to the force acting between surfaces sliding past one another.
c. acts in a direction that opposes the motion of an object.
d. all of the above
e. none of the above
23.
A 15-N force and a 45-N force act on an object in opposite directions. What is the net force on the object?
a. 15 N
b. 30 N
c. 45 N
d. 60 N
e. none of the above
24.
Friction is a force that always acts
a. perpendicular to an object's motion.
b. opposite to an object's motion.
c. in the same direction as an object's motion.
25.
The weight of a person can be represented by a vector that acts
a. in a direction that depends on where the person is standing.
b. perpendicular to the ground underneath the person.
c. parallel to the ground.
d. straight down, even if the person is standing on a hill.
e. all of the above
26.
Which has more mass, a kilogram of feathers or a kilogram of iron?
a. The feathers
b. The iron
c. Neither—they both have the same mass.
27.
A bag of sports equipment has a mass of 10.0 kilograms and a weight of
a. 0.98 N.
b. 9.8 N.
c. 98 N.
d. 980 N.
e. none of the above
28.
If your automobile runs out of fuel while you were driving the engine stops but you do not come to an
abrupt stop. The concept that most explain why is:
A. inertia.
B. gravity.
C. acceleration.
D. resistance.
29.
According to Newton’s First Law, a railroad train in motion should continue going forever even if its
engine in turned off. We never observe this because railroad trains:
A. move too slowly.
B. must go up and down hills.
C. are much too heavy.
D. always have forces that oppose that motion.
30.
If no external forces are acting on a moving object it will
A. continue moving at a constant speed.
B. continue moving at the same velocity
C. move slower and slower until it finally stops
31.
A kilogram is a measure of an object’s:
A. weight.
B. force.
C. mass.
D. size.
32.
Compared to a 1 kg block of solid iron, a 2 kg block of solid iron has twice as much:
A. inertia.
B. mass.
C. volume.
D. all of these.
E. none of these.
33.
Your weight is:
A. equal to your mass
.
B. the gravitational attractive force between you and the earth.
C. a property of mechanical equilibrium.
D. all of these.
34.
If one object has twice as much mass as another object, it also has twice as much:
A. inertia.
B. velocity.
C. acceleration due to gravity. D. all of these.
35.
Strange as it may seem, it is just as hard to accelerate a car on a level surface on the moon as it is here on
the Earth. This is because:
A. the mass of the car is independent of gravity.
B. the weight of the car is independent of gravity.
C. A car is much more easily accelerated on the moon than on the Earth.
36.
In which case would you have the largest mass of gold? If your chunk of gold weighed 1 N on the:
A. moon.
B. Earth.
C. planet Jupiter.
37.
A rock weighs 30 N on Earth. A second rock weighs 30 N on the moon. Which of the two rocks has the
greater mass?
A. the one on the Earth.
B. the one on the moon.
C. they have the same mass.
D. not enough information to say.
38.
If an object’s mass is decreasing while a constant force is applied to the object, the acceleration:
A. decreases.
B. increases.
C. remains the same.
39.
The force of friction on a sliding object is 10 N. The applied force needed to maintain a constant velocity
is:
A. more than 10 N
B. less than 10 N C. 10 N
40.
Whenever the net force on an object is zero, its acceleration:
A. may be less than zero.
B. is zero.
C. may be more than zero.
41.
The maximum acceleration of a car while towing a second car twice its mass, compared to its acceleration
with no car is tow, is:
A. one half.
B. one third.
C. one fourth.
D. the same.
E. none of these.
43.
Your car is coasting on level ground at 60 km/hr and you apply the brakes until the car has slowed to 40
km/hr. If you suddenly release the brakes now, the car tends to:
A. momentarily regain its higher initial speed.
B. continue moving at 40 km/hr.
C. decrease in speed if no other forces act.
44.
A bag of groceries has a mass of 10 kg and a weight of:
A. about 1 N.
B. about 10 N. C. about 100 N.
D. about 1000 N.
45.
The mass of a pet turtle that weighs 10 N is:
A. about 1 kg.
B. about 10 kg. C. about 100 kg. D. about 1000 kg.
46.
A 10 N block and a 1 N block lie on a horizontal frictionless table. To provide them with equal horizontal
acceleration, we would have to push with:
A. equal forces on each block.
B. 10 times as much force on the heavier block.
C. 10 squared or 100 times as much force on the heavier block.
D. 1/10 as much force on the heavier block.
E. none of these.
47.
A baseball player bats a ball with a force of 1000 N. The reaction force that the ball exerts against the bat
is:
A. less than 1000 N.
B. more than 1000 N.
C. 1000N.
D. impossible to determine.
48.
As a ball falls, the action force is the pull of the Earth’s mass on the ball. The reaction force is the:
A. air resistance acting against the ball.
B. acceleration of the ball.
C. pull of the ball’s mass on the Earth
D. none of these.
49.
A person is attracted toward the center of the Earth by a 500 N gravitational force. The Earth is attracted
toward the person with a force of:
A. zero.
B. 250 N
C. 500 N.
D. 1000 N.
50.
An automobile and a baby carriage traveling at the same speed collide head-on. The impact force is:
A. greater on the automobile.
B. greater on the baby carriage.
C. the same for both.
51.
A car traveling at 100 km/hr strikes an unfortunate bug and splatters it. The force of impact is:
A. greater on the bug.
B. greater on the car.
C. the same on both.
52.
A piece of rope is pulled by two people in a tug-of-war. Each pulls with 400 N of force. What is the
tension in the rope?
A. zero.
B. 400 N.
C. 800 N.
D. none of these.