physics part 3 (STUDY!!!)

Look at the data sample below. It is a graph of spring flight distance (cm) versus length of the stretched spring(cm). If you stretched the spring to the 8 cm mark, how far would it fly? a) 8cm b)10cm c)20cm

b. 10cm

19. Velocity is different from speed in that velocity is speed in a given direction.

true

Even though a car is slowing down, it is still accelerating, in the most general definition of acceleration.

true

A ball is thrown straight up. At the top of its path its instantaneous speed is a.0 m/s. b.about 5 m/s. c.about 10 m/s. d.about 20 m/s. e.about 50 m/s.

a. 0 m/s

An object travels 5 meters in the first second of travel, 5 meters again during the second second of travel, and 5 meters again during the third second. Its acceleration is a.0 m/s2. b.5 m/s2. c.10 m/s2. d.15 m/s2. e.none of the above

a. 0 m/s2

As an object falls freely in a vacuum, its a.velocity increases. b.acceleration increases. c.both A and B. d.none of the above.

a. both A and B

Suppose a station wagon is moving in a straight line and steadily increases its speed. It moves from 25 km/h to 30 km/h the first second and from 30 km/h to 35 km/h the next second. What is the station wagon's acceleration? a.10 km/h·s b.5 km/h·s c.30 km/h·s d.25 km/h·s e.35 km/h·s

b. 5 km/h*s

A minivan accelerates at 3 m/s2. Assuming the minivan starts from rest, how much time does it need to accelerate to a speed of 24 m/s? a.3 seconds b.8 seconds c.24 seconds d.48 seconds e.none of the above

b. 8 seconds

If a projectile is fired straight up at a speed of 40 m/s, the total time to return to its starting point is about a.4 seconds. b.8 seconds. c.40 seconds. d.80 seconds. e.not enough information to estimate.

b. 8 seconds

Suppose an object is in free fall. Each second the object falls a.the same distance as in the second before. b.a larger distance than in the second before. c.with the same instantaneous speed. d.with the same average speed. e.none of the above

b. a larger distance than in the second before

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

b. about 10 m/s

Consider drops of water leaking from a water faucet. As the drops fall they a.remain at a relatively fixed distance from each other. b.get farther apart. c.get closer together.

b. get farther apart

Suppose you take a trip that covers 240 km and takes 6 hours to make. Your average speed is a.240 km/h. b.480 km/h. c.40 km/h. d.20 km/h. e.1440 km/h.

c. 40 km/h

A ball is thrown straight up. At the top of its path its acceleration is a.0 m/s2. b.about 5 m/s2. c.about 10 m/s2. d.about 20 m/s2. e.about 50 m/s2.

c. about 10 m/s2

When something falls to the ground, it accelerates. This acceleration is called the acceleration due to gravity and is symbolized by the letter g. What is the value of g on Earth's surface? a.0 m/s2 b.about 5 m/s2 c.about 10 m/s2 d.about 20 m/s2 e.about 50 m/s2

c. about 10 m/s2

In the absence of air resistance, objects fall at constant a.speed. b.velocity. c.acceleration. d.distances each successive second. e.all of the above

c. acceleration

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 downward. d.directed upward.

c. directed downward

Suppose you are in a car that is going around a curve. The speedometer reads a constant 30 miles per hour. Which of the following is NOT true? a.You and the car are accelerating. b.Your acceleration is constantly changing. c.Your velocity is constant. d.Your direction is constantly changing. e.Your speed is constant.

c. your velocity is constant

A freely falling object starts from rest. After falling for 13 seconds, it will have a speed of about a.more than 650 m/s. b.650 m/s. c.65 m/s. d.130 m/s. e.13 m/s.

d. 130 m/s

When a basketball player jumps to make a shot, once the feet are off the floor, the jumper's acceleration a.varies with body orientation. b.depends on launch speed. c.is usually greater for taller players (but not always). d.depends on all the above. e.is g; no more, no less.

e. is g, no more, no less

18. Average speed is defined as the time it takes for a trip divided by the distance.

false

As a ball falls freely, the distance it falls each second is the same.

false

When a car rounds a corner at a constant speed, its acceleration is zero.

false