AP Physics 1 Semester 1 Final Multiple Choice

Which of the following situations represents a negative displacement? (Assume positive position is measured vertically upward along a y-axis.)

A cat jumps from a tree limb to the ground.

Which of the following units is the SI unit of velocity

meter per second

Moustapha Jones drives east at 100km/hr for 3 hours then back west at 80km/hr for 1.5 hours. Which pair of answers gives his average speed and average velocity?

93.3km/hr, 40km/hr east

The driver of a car traveling at 110 km/hr slams on the brakes so the car undergoes a constant acceleration, skidding to a complete stop in 4.5s. What is the average acceleration of the car during braking?

6.79m/s^2

If the car skids in a straight line for the entire length of the stopping distance, how long are its skid marks?

70m

Suppose you are given a position versus time graph. The slope of a line drawn tangent to a point on the curve of this graph describes what quantity?

instantaneous velocity

Acceleration is defined as

the rate of change of velocity.

If you know the acceleration of a car, its initial velocity, and the time interval, which of the following can you predict?A. The direction of the car's initial velocity B. The magnitude of the car's final velocity C. The displacement of the car D. All of the above

all of the above

When a car's velocity is positive and its acceleration is negative, what is happening to the car's motion?

The car slows down.

Moustapha Jones reaches the bottom of a hill on his bike moving at a speed of 8.6 m/s when his chain breaks. He coasts up the hill until he comes to a stop after 3.5 s. Find his acceleration while on the hill, and the distance he travelled up the hill.

-2.46m/s^2, 15.1m

When a car's velocity is negative and its acceleration is negative, what is happening to the car's motion?

The car speeds up.

If you run a complete loop around an outdoor track (400 m), in 100 s, your average velocity is

zero

An object is released from rest on a planet that has no atmosphere. The object falls freely for 3.0 meters in the first second. What is the magnitude of the acceleration due to gravity on the planet?

6m/s^2

Acceleration due to gravity is also called

free-fall acceleration

Which of the following statements applies to the motion of a ball rising and then falling in free fall? I. The ball has constant acceleration as it moves upward. II. The ball has constant acceleration at the top of its path. III. The ball has constant acceleration as it moves downward

I, II, and III

A baseball catcher throws a ball vertically upward and catches it in the same spot as it returns to the mitt. At what point in the ball's path does it experience zero velocity and nonzero acceleration at the same time?

at the top of its path

Which would hit the ground first if dropped from the same height in a vacuum—a feather or a metal bolt?

they would hit the ground at the same time

When an object is released from rest and falls in the absence of friction, which of the following is true concerning its motion?

its acceleration is constant

Suppose a ball is thrown straight up. Make a statement about the velocity and the acceleration when the ball reaches the highest point.

Its velocity is zero and its acceleration is not zero.

Suppose a ball is thrown straight up. What is its acceleration just before it reaches its highest point?

exactly g

Suppose a ball is thrown straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is going up.

Its velocity points upward and its acceleration points downward.

A ball is thrown straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is coming down.

Both its velocity and its acceleration point downward.

Suppose a ball is thrown downward in the absence of air resistance. Make a statement concerning its acceleration.

its acceleration is constant

A ball is thrown vertically upward with a speed v. An identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the second ball to that of the first ball? (How many times higher does the second ball go than the first ball?)

4:1

Ball A is dropped from the top of a building. One second later, ball B is dropped from the same building. As time progresses, the distance between them

increases

Ball A is dropped from the top of a building. One second later, ball B is dropped from the same building. As time progresses, the difference in their speeds

remains constant

Two objects are thrown from the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the street?

They're traveling at the same speed

A brick is dropped from the top of a building. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

The two bricks accelerate at the same rate.

The path of a projectile through space is called its

trajectory

A soldier throws a grenade horizontally from the top of a cliff. Which of the following curves best describes the path taken by the grenade?

a parabola

Two balls are thrown horizontally. Ball C is thrown with a force of 20 N, and ball D is thrown with a force of 40 N. Assuming all other factors are equal, ball D will fall toward the ground

at the same rate as ball c

Which of the following is the motion of objects moving in two dimensions under the influence of gravity?

projectile motion

Which of the following is an example of projectile motion?

a thrown baseball

Which of the following is not an example of projectile motion?

a hot-air balloon drifting toward Earth

What is the path of a projectile (in the absence of friction)?

a parabola

Which of the following does not exhibit parabolic motion?

a flat piece of paper released from a window

At what angle should a water-gun be aimed in order for the water to land with the greatest horizontal range?

45 degrees

An Olympic athlete throws a javelin at four different angles above the horizontal, each with the same speed: 30°, 40°, 60°, and 80°. Which two throws cause the javelin to land the same distance away?

30° and 60°

A ball is thrown at an original speed of 8.0 m/s at an angle of 35° above the horizontal. What is the speed of the ball when it returns to the same horizontal level?

8 m/s

You are throwing a ball for the second time. If the ball leaves your hand with twice the velocity it had on your first throw, its horizontal range R (compared to your first serve) would be

four times as much

When a football in a field goal attempt reaches its maximum height, how does its speed compare to its initial speed?.

it is less than its initial speed

A stone is thrown horizontally from the top of a tower at the same instant a ball is dropped vertically. Which object is traveling faster when it hits the level ground below?

the stone

A bullet is fired horizontally, and at the same instant a second bullet is dropped from the same height. Ignore air resistance. Compare the times of fall of the two bullets.

They hit at the same time

A plane flying horizontally at a speed of 50.0 m/s and at an elevation of 160 m drops a package. Two seconds later it drops a second package. How far apart will the two packages land on the ground?

100m

A pilot drops a bomb from a plane flying horizontally at a constant speed. Neglecting air resistance, when the bomb hits the ground the horizontal location of the plane will

be over the bomb

A rock is thrown upward at 50 degrees with respect to the horizontal. As it rises, neglecting air drag, its vertical component of velocity

decreases

A rock is thrown upward at 50 degrees with respect to the horizontal. As it rises, neglecting air drag, its horizontal component of velocity

remains unchanged

A stone is thrown horizontally from the top of a cliff. One second after it has left your hand, its vertical distance below the top of the cliff is

0m

Roll a bowling ball off the edge of a table. As it falls, its horizontal component of velocity

Remains constant

A hunter on level ground fires a bullet at an angle of 10 degrees above the horizontal while simultaneously dropping another bullet from the level of the rifle. Which bullet will hit the ground first?

the dropped one

A hunter on level ground fires a bullet at an angle of 2 degrees below the horizontal while simultaneously dropping another bullet from the level of the rifle. Which bullet will hit the ground first?

the fired one

A bullet fired horizontally over level ground hits the ground in 0.5 second. If it had been fired with twice the speed in the same direction, it would have hit the ground in

0.5s

An object is dropped and freely falls to the ground with an acceleration of 1 g. If it is thrown upward at an angle instead, its acceleration will be

1g downward

Two projectiles are fired from ground level at equal speeds but different angles. One is fired at an angle of 30 degrees and the other at 60 degrees. The projectile to hit the ground first will be the one fired at (neglect air resistance).

30 degrees

The statement by Newton that for every action there is an equal but opposite reaction is which of his laws of motion?

third

A man weighing 800 N stands at rest on two bathroom scales so that his weight is distributed evenly over both scales. The reading on each scale is

400N

Which has the greater mass?

an automobile battery

A single force acts on an object. The components of this force act along the +x-axis and the -y-axis. The single force that will bring the object into equilibrium has components that act along the

-x-axis and +y-axis

If no external forces are acting on a moving object, it will

continue moving at the same velocity.

You are pushing a rock along level ground and making the rock speed up. How does the size of the force you exert on the rock compare with the size of the force the rock exerts on you? The force you exert

is the same size as the force the rock exerts on you.

A person is attracted toward the center of Earth by a 500-N gravitational force. The Earth is attracted toward the person with a force of

500N

Newton's third law of motion involves the interactions of

two objects and two forces

A kilogram is a measure of an object's

mass

Compared to the mass of a certain object on Earth, the mass of the same object on the moon is

the same

A late traveler rushes to catch a plane, pulling a suitcase with a force directed 30.0° above the horizontal. If the horizontal component of the force on the suitcase is 60.6 N, what is the force exerted on the handle?

70N

A newton is equivalent to which of the following quantities?

kgm/s^2

As an object falls toward Earth,

the upward acceleration of Earth is negligible because of its large mass.

A force is a vector quantity because it has both

magnitude and direction

A car goes forward along a level road at constant velocity. The additional force needed to bring the car into equilibrium is

zero

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

the mass of the car is independent of gravity.

An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the

arrow's push against the bowstring

Which of the following is the tendency of an object to maintain its state of motion?

inertia

A player catches a ball. Consider the action force to be the impact of the ball against the player's glove. The reaction to this force is the

force the glove exerts on the ball

If your automobile runs out of fuel while you are driving, the engine stops but you do not come to an abrupt stop. The concept that most explains why is

inertia

The force of friction on a sliding object is 10 N. The applied force needed to maintain a constant velocity is

10N

The magnitude of the gravitational force acting on an object is

weight

An object in mechanical equilibrium is an object

has no acceleration, is at rest, or moving with constant velocity (all of these)

In which case would you have the largest mass of gold? If your chunk of gold weighed 1 N on the

moon

Your weight is

the gravitational attraction force between you and the Earth.

A skydiver falls towards the Earth. The attraction of the Earth on the diver pulls the diver down. What is the reaction to this force?

water resistance that will soon act upward on the diver, the attraction to the planets, stars, and every particle in the universe, air resistance the diver encounters while falling, all of the above (none of these)

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?

the one on the moon

A baseball player bats a ball with a force of 1000 N. The reaction force that the ball exerts against the bat is

1000N

A free-body diagram represents all of the following except

forces exerted by the object.

When a woman stands at rest with both feet on a scale, it reads 500 N. When she gently lifts one foot, the scale reads

500N

Compared to a 1-kg block of solid iron, a 2-kg block of solid iron has the same

inertia, mass, volume (none of these)

If one object has twice as much mass as another object, it also has twice as much

inertia

Hang from a pair of gym rings and the upward support forces of the rings will always

add up to equal your weight

When a rocket ship accelerating in outer space runs out of fuel, it

no longer accelerates

A hockey stick hits a puck on the ice. Identify an action-reaction pair in this situation.

The stick exerts a force on the puck; the puck exerts a force on the stick.

The length of a force vector represents the

magnitude of the force

A change in the gravitational force acting on an object will affect the object's

weight

A 10-kg brick and a 1-kg book are dropped in a vacuum. The force of gravity on the 10-kg brick is

10 times as much

A 300-kg bear grasping a vertical tree slides down at constant velocity. The friction force between the tree and the bear is

3000N

A hammer drives a nail into a piece of wood. Identify an action-reaction pair in this situation.

The hammer exerts a force on the nail; the nail exerts a force on the hammer.

When riding in an elevator on a bathroom scale, the scale will give a value equal to your true weight when the elevator (choose all that apply)

moves at constant speed, is at rest

When riding in an elevator on a bathroom scale, the scale will give a value smaller than your true weight when the elevator

accelerates downwards

When riding in an elevator on a bathroom scale, the scale will give a value larger than your true weight when the elevator (choose all that apply)

starts its upwards journey

starts its upwards journey, is stopping on the way down

According to Newton's second law, when the same force is applied to two objects of different masses,

the object with greater mass will experience a smaller acceleration, and the object with less mass will experience a greater acceleration.

A 67 kg man rides in an elevator while standing on a bathroom scale calibrated to read force in Newtons. As the elevator moves downwards at a constant speed the scale displays:

656.7N

A 63 kg man rides in an elevator while standing on a bathroom scale calibrated to read force in Newtons. As the elevator moves upwards it slows with an acceleration of magnitude 1.9m/s2. The scale displays:

497.7N