Force and Motion Test Review Questions

Vocabulary

two or more unequal forces acting on an object, causing the object to accelerate

A toy car is placed at the top of a hill and it rolls down the hill. What force causes the car to roll down the hill and what force causes the car to stop?

Review Questions

State the number of Newton’s law that applies to the following example.

• Members of a bobsled team are not satisfied with the speed of their bobsled starts. Each member spends six months at a gym working on building muscle. Six months later, they find that they can accelerate their sled much more quickly.

Vocabulary

Tendency of a moving object to stay in motion or a resting object to stay still

Vocabulary

rubbing force that acts against the motion between two touching surfaces and always slows an object down

Vocabulary

two or more equal forces whose effects cancel each other out and do not change the motion of an object

Every time your cat’s paw hits her toy string, it swings away from her. How does this demonstrate Newton’s third law of Motion?

a.Objects with mass, such as your cat’s paw and toy string, will require inertia.

b.For every action your cat makes, there is an equal and opposite reaction from the string.

c.Objects in action, such as the toy string, will experience force.

d.For every motion from your cat’s paw, there is unbalanced inertia from the string.

Vocabulary

• rate at which the position of an object changes

Review Questions

A ski racer loses a ski when he falls at the bottom of the hill. His body stops moving, but the ski keeps on going because of _______________.

Vocabulary

a force of attraction between objects that is due to their masses

Review Questions

A pool player slams a red ball into a white ball. The red ball stops and the white ball moves. The ___________________ of the red ball was transferred to the white ball.

Vocabulary

the process of changing from one position, or place to another

Vocabulary

a force of attraction between objects that is due to their masses

Two teams are playing tug-of-war. One team pulls to the right with a force of 325 N right and the other team pulls with a force of 375 N left. What is the net force?

a)50 N leftb)50 N rightc)700 N leftd)700 N right

Review Questions• State the number of Newton’s law

that applies to the following example.

• A boy is standing on a bus that is stopped at a stoplight. The bus lurches forward. The upper part of his body is jerked backward.

Vocabulary

rate at which an object’s velocity changes

A girl pulls a canoe into the water with a force of 75N east as another boy pushes it with a force of 90 N east. What is the net force?

a)15 N eastb)165 N eastc)15 N westd)165 N west

What is the relationship between light objects and inertia?

a) Only light objects have inertia.b) Light objects have no inertia.c) Light objects have less inertia than heavy

objects.d) Light objects have more inertia than heavy

objects.

Vocabulary

a push or pull in a particular direction

According to Newton’s Third Law of Motion, when a hammer strikes and exerts force on a nail, the nail…

a) creates a friction with the hammer.b) disappears into the wood.c) exerts an equal force back on the hammer.d) moves at a constant speed.

Three balls are the same size and are dropped from the top of a building. Which ball will hit the ground first?

a. Metal first, then plastic, then wood lastb. Wood first , then plastic, then metal lastc. They will all hit at the same time.d. There is no way to tell.

wood ball Plastic ball metal ball

Review QuestionsState the number of Newton’s law that applies to the following example.

• A pair of campers paddles a canoe across a lake. They dig their paddles into the water and pull them backward. The canoe moves forward.

Your dog’s wagging tail knocks off a glass of water from your coffee table. What kind of force is his tail?

a. an unbalanced forceb. a gravitational forcec. a balanced forced. friction

Vocabulary

rate at which an object moves in a certain direction

Review Questions

Jessie shoots an arrow toward a target. The arrow is moving straight for the target, but _______________________ pulls it to the ground before it reaches the target.

Vocabulary

the combination of all forces acting on an object

Vocabulary

a measure of how difficult it is to stop a moving object; a product of mass and velocity

Review Questions

________________________ slows the fall of a leaf that has just been blown off a tree.

Review Questions

Andy pushes his little brother’s sled along a flat, snowy path. Eventually the sled is stopped by ________________.

Final Question!

• A worker drops his hammer off the roof of a house. The hammer has a mass of 9kg, and gravity accelerates it at the usual 9.8 m/s2. How much force does the earth apply to the hammer?