Chapter 3 (Linear Motion) Test Review

A man leans over the edge of a cliff and throws a rock upward at 4.9 m/s. Neglecting air resistance, one second later the rock's speed is A) zero. B) 4.9 m/s. C) 9.8 m/s. D) 14.7 m/s. E) none of the above

B) 4.9 m/s.

A ball is thrown 125 meters upward and then falls the same distance back to Earth. Neglecting air resistance, its total time in the air is A) about 5 seconds. B) about 10 seconds. C) about 15 seconds. D) more than 20 seconds.

B) about 10 seconds.

If an object moves with constant acceleration, its velocity must A) be constant also. B) change by the same amount each second. C) change by varying amounts depending on its speed. D) always decrease.

B) change by the same amount each second.

A bullet is fired straight down from the top of a high cliff. Neglecting air resistance, the acceleration of the bullet in meters per second per second A) is less than 9.8. B) is 9.8. C) is more than 9.8. D) depends on the height of the cliff.

B) is 9.8.

A ball is thrown upwards and caught when it comes back down. In the presence of air resistance, the speed with which it is caught is always A) more than the speed it had when thrown upwards. B) less than the speed it had when thrown upwards. C) the same as the speed it had when thrown upwards. D) impossible to determine.

B) less than the speed it had when thrown upwards.

Drop a rock from a 5-m height and it accelerates at 10 m/s2 and strikes the ground 1 s later. Drop the same rock from a height of 2.5 m and its acceleration of fall is about A) half as much. B) the same amount. C) twice as much. D) four times as much.

B) the same amount

A ball is thrown upwards and returns to the same position. Compared with its original speed after release, its speed when it returns is about A) half as much. B) the same. C) twice as much. D) four times as much.

B) the same.

When a rock thrown straight upwards gets to the exact top of its path, its A) velocity is zero and its acceleration is zero. B) velocity is zero and its acceleration is about 10 meters per second per second. C) velocity is about 10 m/s and its acceleration is zero. D) velocity is about 10 m/s and its acceleration is about 10 meters per second per second. E) none of these

B) velocity is zero and its acceleration is about 10 meters per second per second.

If you drop an object, it will accelerate downward at a rate of 9.8 meters per second per second. If you instead throw it downwards, its acceleration (in the absence of air resistance) will be A) less than 9.8 meters per second per second. B) 9.8 meters per second per second. C) greater than 9.8 meters per second per second.

B)9.8 meters per second per second.

Disregarding air drag, how fast must you toss a ball straight up in order for it to take 2 seconds to return to the level from which you tossed it? A) 5 m/s B) 7.5 m/s C) 10 m/s D) 15 m/s E) 20 m/s

C) 10 m/s

If a rocket initially at rest accelerates at a rate of 50 m/s2 for one minute, its speed will be A) 50 m/s. B) 500 m/s. C) 3000 m/s. D) 3600 m/s.

C) 3000 m/s

One half second after starting from rest, a freely falling object will have a speed of about A) 20 m/s. B) 10 m/s. C) 5 m/s. D) 2.5 m/s. E) none of these

C) 5 m/s.

It takes 6 seconds for a stone to fall to the bottom of a mine shaft. How deep is the shaft? A) about 60 m B) about 120 m C) about 180 m D) more than 200 m

C) about 180 m ut + 0.5at² (0 * 6) + (0.5 * 10 * 6²) 0 + 180 180

Disregarding air resistance, objects fall with constant A) velocity. B) speed. C) acceleration. D) distances each successive second.

C) acceleration.

A bullet is dropped from the top of the Empire State Building while another bullet is fired downward from the same location. Neglecting air resistance, the acceleration of A) the fired bullet is greater. B) the dropped bullet is greater. C) each bullet is 9.8 meters per second per second.

C) each bullet is 9.8 meters per second per second.

A bullet is dropped into a river from a very high bridge. At the same time, another bullet is fired from a gun, straight down towards the water. Neglecting air resistance, the acceleration just before striking the water A) is greater for the dropped bullet. B) is greater for the fired bullet. C) is the same for each bullet. D) depends on how high they started. E) none of these

C) is the same for each bullet.

Someone standing at the edge of a cliff throws one ball straight up and another ball straight down at the same initial speed. Neglecting air resistance, the ball to hit the ground below the cliff with the greater speed will be A) the one thrown upward. B) the one thrown downward. C) neither -- they will both hit with the same speed.

C) neither -- they will both hit with the same speed.

A car accelerates at 2 meters/s/s. Assuming the car starts from rest, how far will it travel in 10 s? A) 2 m B) 10 m C) 40 m D) 100 m E) 200 m

D) 100 m

A man leans over the edge of a cliff and throws a rock upward at 4.9 m/s. Neglecting air resistance, two seconds later the rock's speed is A) zero. B) 4.9 m/s. C) 9.8 m/s. D) 14.7 m/s. E) none of the above

D) 14.7 m/s.

a car accelerates from rest at 2 meters per second per second, its speed 3 seconds later will be about A) 2 m/s. B) 3 m/s. C) 4 m/s. D) 6 m/s.

D) 6 m/s

At one instant an object in free fall is moving downward at 50 meters per second. One second later its speed should be about A) 25 m/s. B) 50 m/s. C) 55 m/s. D) 60 m/s. E) 100 m/s.

D) 60 m/s.

A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting point. During this time the acceleration of the ball is always A) in the direction of motion. B) opposite its velocity. C) directed upward. D) directed downward.

D) directed downward

Twelve seconds after starting from rest, an object falling freely will have a speed of A) 10 m/s. B) 50 m/s. C) 100 m/s. D) more than 100 m/s.

D) more than 100 m/s

Starting from rest, the distance a freely falling object will fall in 0.5 second is about A) 1 m. B) 10 m. C) 1.00 m. D) none of the above

D) none of the above

Ten seconds after starting from rest, a car is moving at 40 m/s. What is the car's acceleration in meters per second per second? A) 0.25 B) 2.8 C) 4.0 D) 10 E) 40

D)10

While a car travels around a circular track at a constant speed, its A) acceleration is zero. B) velocity is zero. C) inertia is zero. D) none of the above

D)none of the above

a freely falling object were somehow equipped with a speedometer on a planet where the acceleration due to gravity is 20 m/s/s, then its speed reading would increase each second by A) 10 m/s. B) 20 m/s. C) 30 m/s. D) 40 m/s. E) depends on its initial speed

B) 20 m/s.

An object covers a distance of 8 meters in the first second of travel, another 8 meters during the next second, and 8 meters again during the third second. Its acceleration in meters per second per second is approximately A) 0. B) 5. C) 8. D) 24.

A) 0.

If a projectile is fired straight up at a speed of 10 m/s, the time it takes to reach the top of its path is about A) 1 second. B) 2 seconds. C) 10 seconds. D) not enough information to estimate

A) 1 second. g is 10 m/s. Going up an object would lose 10 m/s

one instant a heavy object in air is moving upward at 50 meters per second. One second later its speed is approximately A) 40 m/s. B) 50 m/s. C) 55 m/s. D) 60 m/s.

A) 40 m/s.

A pot falls from a ledge and hits the ground 45 m below. The speed with which it hits the ground is (Hint: use the formula for "t", then use the result in the formula for "v") A) about 30 m/s. B) about 60 m/s. C) about 120 m/s. D) more than 120 m/s.

A) about 30 m/s.

A ball is thrown upwards. Neglecting air resistance, what initial upward speed does the ball need to remain in the air for a total time of 10 seconds? A) about 50 m/s B) about 60 m/s C) about 80 m/s D) about 100 m/s E) about 110 m/s

A) about 50 m/s

While an object near the Earth's surface is in free fall, its A) velocity increases. B) acceleration increases. C) mass increases. D) mass decreases.

A) velocity increases

A car maintains a constant velocity of 100 km/hr for 10 seconds. During this interval its acceleration is A) zero. B) 10 km/hr. C) 110 km/hr. D) 1000 km/hr.

A) zero. If velocity is constant than acceleration is 0

a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by about A) 5 m/s. B) 10 m/s. C) 15 m/s. D) a variable amount. E) depends on its initial speed

B) 10 m/s

An apple falls from a tree and hits the ground 5 meters below. It hits the ground with a speed of about (Hint: use the formula for "t", then use the result in the formula for "v") A) 5 m/s. B) 10 m/s. C) 15 m/s. D) 20 m/s. E) not enough information given to estimate

B) 10 m/s.

A car accelerates at 2 meters per second per second. Assuming the car starts from rest, how much time does it need to accelerate to a speed of 30 m/s? A) 2 seconds B) 15 seconds C) 30 seconds D) 60 seconds E) none of these

B) 15 seconds

If a projectile is fired straight up at a speed of 10 m/s, the total time to return to its starting position is about A) 1 second. B) 2 seconds. C) 10 seconds. D) 20 seconds. E) not enough information to estimate

B) 2 seconds.

A horse gallops a distance of 10 kilometers in a time of 30 minutes. Its average speed is A) 15 km/h. B) 20 km/h C) 30 km/h D) 40 km/h

B) 20 km/h