Acd. Physics Chapter 2 - 3

A ball is thrown straight up. At the top of its path its acceleration is. A. 0 m/s/s B. about 5 m/s/s C. about 10 m/s/s D. about 20 m/s/s

A

An object travels 8 meters in the first second of travel, 8 meters again during the 2nd second of travel, and 8 meters again during the third second. Its acceleration is... A. 0 m/s/s B. 8 m/s/s C. 16 m/s/s D. 32 m/s/s E. None of the above

A. 0 m/s/s

Jose can jump vertically 1 meter from his skateboard when it is at rest. When the skateboard is moving horizontally, Jose can jump. A. No higher B. higher

A. No higher

In Chapter 2 we learned about "hang time", the time a jumper's feet are off the ground in a vertical jump. If the jumper runs horizontally and has the same vertical component ot takeoff velocity, hang time will be. A. no different B. increased C. decreased.

A. no different.

When in orbit, a satellite like the Space Shuttle is... A. simply a projectile. B. Free from the earth's gravity C. in non-acceleration.

A. simply a projectile.

A cannonball is fired at some angle into the air. In the first second it moves 10 meters horizontally. Assuming it doesn't hit the ground and air resistance is small, how far does it move horizontally in the next second? A. More than 10 m B. 10 m C. Less then 10 m D. There's not enough information to say.

B. 10 M

A car acceleration at 2 m/s/s. Assuming the car starts from rest, how much time does it need to accelerate to speed of 30 m/s/s A. 2 seconds B. 15 seconds C. 30 seconds D. 60 seconds E. None of the above.

B. 15 seconds

A ball is thrown straight upward at 20 m/s/s. Ideally (no air resistance), the ball will return to the thrower's hand with a speed of... A. 40 m/s B. 20 m/s C. 10 m/s D. 0 m/s E. There is not enough information to tell.

B. 20 m/s

If an object were equipped with a speedometer and allowed to fall freely on a planet where the acceleration due to gravity is 20 m/s/s, the reading on the speedometer increases each second by... A. 10 m/s B. 20 m/s C. 30 m/s D. 40 m/s E. a rate that depends on it initial speed.

B. 20 m/s

A vector is quantity that has... A. Magnitude and time B. Magnitude and direction C. Time and direction.

B. Magnitude and direction.

If you could throw a baseball horizontally at a speed of 8 km/s and if there is no air drag and nothing to stop it... A. it would escape the earth B. Wait 90 minutes and it would return to you.

B. Wait 90 minutes and it would return to you.

In the absence of air resistance, objects fall at constant... A. Velocity B. Speed C. Acceleration D. Distances each successive second. E. All of the above.

C. Acceleration

At the instant a ball is thrown horizontally with a large force, an identical ball is dropped from the same height. Which ball hits the ground first? A. The horizontally thrown ball. B. The dropped ball C. Neither -- they both hit the ground at the same time.

C. Neither -- they both hit the ground at the same time.

A ball is thrown upwards and caught when it come back down. In absence of air resistance, the speed of the ball when caught would be... A. More then the speed it had when thrown upwards. B. Less then the speed it had when thrown upwards C. The same as the speed it had when thrown upwards.

C. The same as the speed it had when thrown upwards.

After a rock that is thrown straight up reaches the top of its path and is starting to fall back down, it acceleration is (neglect air resistance)... A. Greater than when it was at the top of its path. B. Less than when it was at the top of its path. C. The same as when it was at the top of its path.

C. The same as when it was at the top of its path

When something falls to the ground, it accelerates. This acceleration is called the acceleration due to gravity and symbolized by the letter g. What is the value of g on the earth's surface? A. 0 m/s/s B. about 5 m/s/s C. about 10 m/s/s D. about 20 m/s/s E. about 50 m/s/s

C. about 10 m/s/s

Speed is... A. A measure of how fast something is moving. B. The distance covered per unit. C. Always measured in terms of a unit of distance divided by a unit of time. D. All of that above. E. None of the above.

D. All of the above.

Suppose you take a trip that covers 240 km and takes 4 hours to make. Your average speed is... A. 960 km/h B. 480 km/h C. 240 km/h D. 120 km.h E. 60 km/h

E. 60 km/h