Exam #1 (M) (Mechanics)

In a drill during basketball practice, a player runs the length of the 30.-meter court and back. The player does this three times in 60. seconds.

• 0.0 m/s

• 0.50 m/s

• 3.0 m/s

• 30. m/s

What is the average speed of an object that travels 6.00 meters north in 2.00 seconds and then travels 3.00 meters east in 1.00 second?

• 9.00 m/s

• 0.333 m/s

• 3.00 m/s

• 4.24 m/s

A rock dropped off a bridge takes 5 seconds to hit the water. Approximately what was the rock's velocity just before impact?

• 5 m/s

• 2 m/s

• 125 m/s

• 50 m/s

As shown in the diagram below, an astronaut on the Moon is holding a baseball and a balloon. The astronaut releases both objects at the same time.

• The baseball falls slower than the balloon.

• The baseball and balloon fall at the same rate.

• The baseball falls faster than the balloon.

• The baseball and balloon remain suspended and do not fall.

What is the speed of a 2.5-kilogram mass after it has fallen freely from rest through a distance of 12 meters?

• 15 m/s

• 4.8 m/s

• 30. m/s

• 43 m/s

The graph below shows speed as a function of time for four cars A, B, C, and D, in straight-line motion.

• Car A

• Car B

• Car C

• Car D

A 12.0-kilogram cart is moving at a speed of 0.25 meter per second. After the speed of the cart is tripled, the inertia of the cart will be

• unchanged

• one-third as great

• three times greater

• nine times greater

A ball at rest was dropped from 100 m high cliff where are the free fall acceleration is 9.81 m/s/s. Find a velocity when the ball hit the ground.

Jessica is walking towards east 20 meters and then she walked south 10 meter. Calculate the displacement.

Put your answer in the correct significant figure. What is

 $10.3\ \div\ 1.2222\$