Physics Chapter 3

The distance a freely falling bowling ball falls each second Select one: a. is about 10 m. b. None of these c. is about 5 m. d. increases.

increases.

A cart maintains a constant velocity of 100 m/s for 10 seconds. During this interval its acceleration is Select one: a. 1 m/s2. b. None of these c. zero. d. 10 m/s2.

zero

Phil leans over the edge of a cliff and throws a rock upward at 5 m/s. Neglecting air resistance, two seconds later the rock's speed is Select one: a. zero. b. 15 m/s. c. None of these d. 10 m/s. e. 5 m/s.

15 m/s.

The time it takes a car to attain a speed of 30 m/s when accelerating from rest at 2 m/s2 is Select one: a. 30 s. b. 60 s. c. 2 s. d. 15 s e. None of these

15 s

Ten seconds after starting from rest, a car is moving at 40 m/s. What is the car's acceleration? Select one: a. 10 m/s2 b. 4.0 m/s2 c. 2.8 m/s2 d. 0.25 m/s2 e. 40 m/s2

4.0 m/s2 (NOT 40- be careful!)

A freely-falling watermelon falls with constant Select one: a. speed. b. velocity. c. acceleration. d. distances each successive second.

acceleration.

The accelerations possible for a ball on an inclined plane Select one: a. range from g to infinity. b. range from zero to g. c. have no limit.

range from zero to g.

Which of the following is not a vector quantity? Select one: a. none are vector quantities. b. speed c. all are vector quantities d. velocity e. acceleration

speed

An object at rest near the surface of a distant planet starts to fall freely. If the acceleration there is twice that of the Earth, its speed one second later would be Select one: a. 30 m/s. b. 10 m/s. c. 20 m/s. d. 40 m/s.

20 m/s.

At one instant an object in free fall is moving downward at 50 m/s. One second later its speed is Select one: a. 100 m/s. b. 50 m/s. c. 55 m/s. d. 25 m/s. e. 60 m/s.

60 m/s.

The speedometer of an automobile reads Select one: a. accelerated speed. b. average speed. c. instantaneous speed.

instantaneous speed.

Neglecting air resistance, how fast must you toss a ball straight up in order for it to take 6 seconds to return to its initial level? Select one: a. 5 m/s b. 10 m/s c. 20 m/s d. more than 30 m/s e. 30 m/s

30 m/s

The two measurements necessary for calculating average speed are Select one: a. velocity and time. b. distance and time. c. acceleration and time. d. distance and acceleration. e. velocity and distance.

distance and time.

A motorboat that normally travels at 8 km/h in still water heads directly across a 6-km/h flowing river. The resulting speed of the boat is about Select one: a. 10 km/h. b. 6 km/h. c. 20 km/h. d. 8 km/h.

10 km/h.

The total time it takes a projectile fired straight up at 10 m/s to reach the top of its path and return to its starting point is about Select one: a. 2 s. b. 10 s. c. 20 s. d. 1 s.

2 s.

At one instant a heavy object in air is moving upward at 50 m/s. One second later its speed is approximately Select one: a. 60 m/s. b. 50 m/s. c. 55 m/s. d. 40 m/s.

40 m/s.

Jogging Jake runs at 4 m/s along a train flatcar that moves at 10 m/s in the opposite direction. Jake's speed relative to the ground is Select one: a. 14 m/s. b. 6 m/s. c. None of these d. 10 m/s.

6 m/s.

Phil leans over the edge of a cliff and throws a rock upward at 5 m/s. Neglecting air resistance, one second later the rock's speed is Select one: a. None of these b. 5 m/s. c. 15 m/s. d. 10 m/s. e. zero.

5 m/s.

The time it takes a projectile fired straight up at 10 m/s to reach the top of its path is about Select one: a. 1 s. b. not enough information c. 10 s. d. 2 s.

1 s.

The vertical height attained by a basketball player who achieves a hang time of a full 1 s is about Select one: a. 2.5 m. b. 1 m. c. 1.2 m. d. 0.8 m. e. more than 2.5 m.

1.2 m.

If a freely falling object were equipped with a speedometer, its speed reading would increase each second by about Select one: a. depends on its initial speed b. 10 m/s. c. a variable amount. d. 15 m/s. e. 5 m/s.

10 m/s.

An 80-km/h airplane caught in a 60-km/h crosswind has a resultant speed of Select one: a. 141 km/h. b. 60 km/h. c. 100 km/h. d. 80 km/h.

100 km/h.

A mosquito flying at 3 m/s that encounters a breeze blowing at 3 m/s in the opposite direction has a speed of Select one: a. 3 m/s. b. 0 m/s. c. 6 m/s. d. 4 m/s.

0 m/s.

When a ball thrown straight upwards reaches the very top of its path, its acceleration is Select one: a. 5 m/s2. b. zero. c. None of these d. 10 m/s2.

10 m/s2.

An 80-km/h airplane flying in the same direction as a 10 km/h tail wind has a groundspeed of Select one: a. 80 km/h. b. 10 km/h. c. 70 km/h. d. 90 km/h.

90 km/h.

Compared with hang time on Earth, hang time on the Moon would be Select one: a. greater. b. less. c. the same.

greater.

Twelve seconds after starting from rest, a freely-falling cantelope has a speed of Select one: a. 10 m/s. b. 100 m/s. c. more than 100 m/s. d. 50 m/s.

more than 100 m/s.

The muzzle velocity of a bullet fired from a new rifle is 100 m/s. Neglecting air resistance, at the end of one second a bullet fired straight up into the air will have traveled a distance of Select one: a. 5 m. b. (100 - 5) m. c. None of these d. (100 + 5) m. e. 100 m.

(100 - 5) m.

Phil leans over the edge of a cliff and throws a rock upward at 5 m/s. How far below the level from which it was thrown is the rock 2 seconds later? Select one: a. 20 m b. 15 m c. 10 m d. 5 m

10 m

A ball starting from rest at the top of an inclined plane gains a speed of 2 m/s for each second it rolls. What is its acceleration down the incline? Select one: a. 1 m/s2 b. 0.5 m/s2 c. 4 m/s2 d. 2 m/s2

2 m/s2

When you walk at an average speed of 4 m/s, in 5 s you'll cover a distance of Select one: a. 2 m. b. 15 m. c. 20 m. d. 10 m.

20 m.

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 Select one: a. in the direction of motion. b. None of these c. directed upward. d. opposite its velocity. e. directed downward.

directed downward.

A bird flying at 8 km/h in a 6-km/h crosswind has a resultant speed of Select one: a. 8 km/h. b. 14 km/h. c. 6 km/h. d. 10 km/h.

10 km/h.

An apple falls from a tree and hits the ground 5 meters below with a speed of about Select one: a. 5 m/s. b. 20 m/s. c. 15 m/s. d. not enough information e. 10 m/s.

10 m/s.

A river 100 m wide flows due south at 1 m/s. A boat that travels 1 m/s relative to the water is pointed due east as it crosses from the west bank. The boat reaches the east bank Select one: a. 100 m farther south. b. None of these c. 141 m farther south.Incorrect d. due east of its starting point.

100 m farther south.

An object falls freely from rest on a planet where the acceleration due to gravity is 20 m/s2. After 5 seconds, the object will have a speed of Select one: a. 50 m/s. b. 20 m/s. c. 100 m/s. d. 5 m/s. e. 10 m/s.

100 m/s.

Neglecting air resistance, a ball projected straight upward so it remains in the air for 10 seconds needs an initial speed of Select one: a. 100 m/s. b. 110 m/s. c. 80 m/s. d. 50 m/s. e. 60 m/s.

50 m/s.

While an iron block near the Earth's surface is in free fall, it undergoes an increase in Select one: a. speed. b. acceleration. c. neither of these d. both of these

speed.

The average speed of a horse that gallops 10 kilometers in 30 minutes is Select one: a. 15 km/h. b. 20 km/h. c. 40 km/h. d. 30 km/h.

20 km/h.

What is the acceleration of a car that starts from rest and 5 seconds later reaches a speed of 20 m/s? Select one: a. 4 m/s2 b. 1 m/s2 c. 3 m/s2 d. 2 m/s2 e. 5 m/s2

4 m/s2

A humming bird flying at 4 km/h that gets caught in a 3-km/h crosswind has a resultant speed of about Select one: a. 5 km/h. b. 4 km/h. c. more than 5 km/h. d. 3 km/h.

5 km/h.

If you throw a ball straight downward (in the absence of air resistance), after leaving your hand its acceleration is Select one: a. less than 10 m/s2. b. greater than 10 m/s2. c. 10 m/s2.

10 m/s2.

Neglecting air resistance, a bullet fired straight down from the top of a high cliff has an acceleration of Select one: a. depends on the height of the cliff. b. 10 m/s2. c. more than 10 m/s2. d. less than 10 m/s2.

10 m/s2.

An object falls freely from rest on a planet where the acceleration due to gravity is twice as much as on Earth. In the first 5 seconds it falls a distance of Select one: a. 500 m. b. 150 m. c. None of these d. 100 m. e. 250 m.

250 m.

A pot that falls from a ledge and hits the ground 45 m below hits the ground at Select one: a. 120 m/s. b. 30 m/s. c. 60 m/s. d. more than 120 m/s.

30 m/s.

One half second after starting from rest, a freely falling object will have a speed of about Select one: a. 20 m/s. b. 2 m/s. c. 10 m/s. d. None of these e. 5 m/s.

5 m/s.

A mosquito flying at 3 m/s that encounters a breeze blowing at 3 m/s in the same direction has a speed of Select one: a. 3 m/s. b. 0 m/s. c. 4 m/s. d. 6 m/s.

6 m/s.

A ball starting from rest at the top of an inclined plane accelerates at 2 m/s2 and reaches the bottom of the plane in 3 seconds. What is the length of the plane? Select one: a. 9 m b. 5 m c. 3 m d. 2 m

9 m

Jogging Jake runs at 4 m/s along a train flatcar that moves at 10 m/s in the same direction. Jake's speed relative to the ground is Select one: a. 14 m/s. b. 6 m/s. c. None of these d. 10 m/s.

14 m/s.

A river 100 m wide flows 1 m/s due south. A boat that travels 1 m/s relative to the water is pointed due east as it crosses from the west bank. Relative to its starting point, the boat travels Select one: a. 100 m. b. 200 m. c. 141 m. d. more than 200 m. e. nowhere.

141 m.

If a stone falls to the bottom of a mineshaft in 6 seconds, then the depth of the shaft is about Select one: a. 60 m. b. 180 m. c. 120 m. d. more than 200 m.

180 m.

If a car increases its velocity from zero to 60 m/s in 10 seconds, its acceleration is Select one: a. 6 m/s2. b. 600 m/s2. c. 60 m/s2. d. 3 m/s2.

6 m/s2.

An 80-km/h airplane flying against a 10-km/h head wind has a groundspeed of Select one: a. 90 km/h. b. 70 km/h. c. 10 km/h. d. 80 km/h.

70 km/h.

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 is Select one: a. 8 m/s2. b. 0 m/s2. c. 24 m/s2. d. 5 m/s2.

0 m/s2.

A bullet is dropped into a river from a very high bridge at the same time as another bullet is fired straight downward from a rifle. Neglecting air resistance, the acceleration just before striking the water is Select one: a. the same for each bullet. b. greater for the fired bullet. c. None of these d. greater for the dropped bullet.

the same for each bullet.

A cart changes its speed from 90 m/s to 100 m/s in 10 seconds. During this interval its acceleration is Select one: a. 10 m/s2. b. None of these c. 1 m/s2. d. zero.

1 m/s2.

The distance a freely falling object falls from rest in one-half second is Select one: a. 2 m. b. 6 m. c. 4 m. d. None of these

None of these

While a car travels around a circular track at a constant speed, its Select one: a. acceleration is zero. b. None of these c. velocity is zero. d. inertia is zero.

None of these

A seagull flying at 10 km/h in a 10-km/h crosswind has a resultant speed of Select one: a. more than 20 km/h. b. 10 km/h. c. 20 km/h. d. about 14 km/h.

about 14 km/h.

You're at rest in a hammock when a hungry mosquito sees an opportunity for lunch. A mild 2-m/s breeze is blowing. If the mosquito joins you for lunch it should hover over you by flying Select one: a. against the breeze at 2 m/s. b. None of these c. with the breeze at 2 m/s. d. a bit faster than wind speed.

against the breeze at 2 m/s.

Phil Physiker standing at the edge of a cliff throws one ball straight up and another ball straight down, both with the same speed. Neglecting air resistance, which ball hits the ground below with the greater speed? Select one: a. the one thrown upward b. the one thrown downward c. neither, both hit with the same speed

c. neither, both hit with the same speed

If an object moves with constant acceleration, its velocity must Select one: a. be constant also. b. change by the same amount each second. c. change by varying amounts depending on its speed. d. always decrease.

change by the same amount each second.

If a freely falling object were equipped with a speedometer on a planet where the acceleration due to gravity is 20 m/s2, then its speed reading would increase each second by Select one: a. 20 m/s. b. 30 m/s. c. 10 m/s. d. 40 m/s. e. depends on its initial speed

20 m/s.

A ball is projected 125 meters straight upward and then falls the same distance back to its starting point. Neglecting air resistance, its total time in the air is about Select one: a. 5 s. b. more than 20 s. c. 15 s. d. 10 s

10 s

An airplane that flies at 100 km/h in a 100-km/h crosswind has a ground speed of Select one: a. 0 km/h. b. 200 km/h. c. 141 km/h. d. 100 km/h.

141 km/h.

A ball rolls along a horizontal track in a certain time. If the track has a small upward dent in it, the time to roll the length of the track will be Select one: a. less. b. more. c. the same.

more.

If a rocket initially at rest accelerates at a rate of 50 m/s2 for one minute, its speed will be Select one: a. 3600 m/s. b. 500 m/s. c. 3000 m/s. d. 50 m/s.

3000 m/s.

A car's speed 3 seconds after accelerating from rest at 2 m/s2 is Select one: a. 4 m/s. b. 2 m/s. c. 6 m/s. d. 3 m/s.

6 m/s.

A rock dropped from a 5-m height accelerates at 10 m/s2 and strikes the ground 1 s later. If the rock is dropped from a height of 2.5 m, its acceleration of fall is Select one: a. half. b. four times as much. c. twice. d. the same.

the same.

As water drops fall at a steady rate from a leaking faucet they Select one: a. get closer together. b. remain at a relatively fixed distance from one another. c. get farther apart.

get farther apart.

A ball is thrown upwards and returns to the same location. Compared with its initial speed its speed when it returns is about Select one: a. half as much. b. four times as much. c. twice as much. d. the same.

the same.

A vehicle undergoes acceleration when it Select one: a. loses speed. b. changes its direction. c. gains speed. d. All of these

All of these

A ball rolls along a horizontal track in a certain time. If the track has a dip in it, the time to roll the length of the track will be Select one: a. less. b. the same. c. more.

less.

Katelyn runs along the aisle of a train that moves at 8 m/s. Her speed relative to the floor is 3 m/s. Her speed relative to an observer at rest on the ground is Select one: a. 5 m/s. b. either depending on her running direction c. 11 m/s. d. None of these

either depending on her running direction

If an object falling freely were somehow equipped with an odometer to measure the distance it travels, then the amount of distance it travels each succeeding second would be Select one: a. greater than the second before. b. constant. c. doubled. d. less and less each second.

greater than the second before.