Deck 12: The Conditions of Linear Motion

Question 1

What is inertia?

A) effect of one object on another
B) resistance to change in motion
C) rate of change in motion
D) tendency of an object to rotate

Answer 1

resistance to change in motion

Question 2

How does body weight compare with ground reaction force if the body is quickly accelerated downward into a crouch?

A) body weight greater than ground reaction force
B) ground reaction force greater than body weight
C) magnitudes are equal
D) none of the above

Answer 2

body weight greater than ground reaction force

Question 3

Force is defined as any influence tending to _____ motion.

A) cause
B) change
C) modify
D) a, b, c

Answer 3

a, b, c

Question 4

Which of the following makes it difficult for a runner to change either his speed or direction?

A) torque
B) acceleration
C) inertia
D) velocity

Question 5

Ball A is the same mass as Ball B. If Ball A is hit with twice as much force as Ball B, Ball A's acceleration will be _____ that of Ball B.

A) one-half
B) one-fourth
C) twice
D) four times

Question 6

Which factor contributes to form drag in objects moving through the air or water?

A) displacement
B) total surface area
C) size of object
D) cross sectional area

Question 7

Which of the following represents a force that opposes the forward movement of a swimmer?

A) buoyancy
B) drag
C) lift
D) magnus effect

Question 8

What is the name of the upward force acting on a body submerged in water?

A) buoyancy
B) drag
C) thrust
D) weight

Question 9

Which is true when applying Newton's 3^rd law of action/reaction to dribbling a basketball?

A) action: ball hits floor; reaction: floor pushes ball
B) action: floor pushes ball; reaction: ball hits floor
C) action: ball leaves hand; reaction: ball hits floor
D) action: ball hits floor; reaction: ball force on hand

Question 10

What causes the ball to curve when a pitcher throws a curve ball?

A) difference in the relative speed of the air on different, sides of the ball
B) Ghost of Bernoulli forces the ball to curve
C) form drag on the front of the ball
D) turbulence in the trailing air

Question 11

In which direction does the force of friction act during a runner's standing start?

A) in a vertical direction
B) in the horizontal direction the runner intends to move
C) in the horizontal direction opposite the runner's motion
D) friction has no direction

Question 12

Which of the following statements is correct concerning momentum?

A) given equal linear velocity just after impact, a tennis ball will have greater momentum than a tennis racquet
B) at the same velocity, a badminton racquet will have greater momentum than a tennis racquet
C) a 14 lb. bowling ball with a linear velocity of 35 ft/sec will have greater momentum than a 8 lb. ball at 50 ft/sec
D) a softball bat weighing one-third that of a second bat but swung at twice the velocity will have greater momentum

Question 13

In which of the following must a force always be present?

A) acceleration
B) displacement
C) dynamics
D) motion

Question 14

Change in momentum is the result of an impulse. How may the impulse be changed?

A) distance of backswing
B) power being used
C) time of application of force
D) change kinetics

Question 15

Why is a magician able to pull a tablecloth out from under a table setting without pulling everything onto the floor?

A) friction is overcome by rapid movement of tablecloth
B) inertia of pieces of table setting is greater than the displacing force
C) both a and b
D) this is a magician's trick, it is an illusion

Question 16

What are two primary factors in friction?

A) the surface area and the weight
B) the force pushing two surfaces together and the nature of the surfaces
C) the surface area and the nature of the surfaces
D) the pushing force and the time of contact

Question 17

What is weight?

A) friction times base of support
B) mass times acceleration due to gravity
C) gravitation times density
D) size times base of support

Question 18

Which of the following diagrams illustrate the rebound of the ball with the lowest coefficient of elasticity?

A) Option A
B) Option B
C) Option C
D) Option D

Question 19

What property of an object represents the ability of an object to resist distortion and to return to its original shape?

A) distortion
B) elasticity
C) restitution
D) stress

Question 20

Upon what does the force necessary to overcome the inertia of a projected object depend?

A) mass of object and point of application of the force
B) mass of object and its velocity
C) size of object and speed at which it is moving
D) weight of object and distance it has traveled

Question 21

Why will a steel ball bounce when dropped on a trampoline but not when dropped on a wooden floor?

Question 22

Why does one tend to shorten one's stride when walking on the ice?

Question 23

What happens to the total energy of the system during the interaction of a golf club and golf ball?

A) remains constant
B) increases
C) decreases
D) remains variable

Question 24

Why do one's feet drop if the head is lifted in a face floating position in swimming?

Question 25

Mechanical work involves a _____ and the _____ that it moves through.

A) force, distance
B) distance, velocity
C) speed, distance
D) acceleration, velocity

Question 26

Why is it more difficult to stop a sled carrying 2 people on than to stop a sled carrying 1 person if both have the same velocity?

Question 27

How much work is done if you hold a tennis racquet in your hand without moving it?

A) none
B) a small amount
C) a large amount
D) depends on size of racquet

Question 28

What type of energy is possessed by a projectile with a horizontal velocity at the peak of the path?

A) kinetic
B) potential
C) none
D) a and b
Short Answer Questions

Question 29

Why is it more difficult to run on the beach than on the street?

Question 30

The _____ the time it takes to move a given distance, the greater is the power.

A) greater
B) larger
C) shorter
D) same