Freefall

Which would hit the ground first if dropped from the same height in a vacuum—a feather or a metal bolt?

• the feather

• the metal bolt

• They would hit the ground at the same time.

• They would be suspended in a vacuum.

If a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by

• its rate depends on its initial speed

• about 15 m/s

• about 10 m/s

• about 5 m/s

Which of the following statements applies to the motion of a ball tossed upward?

I. It has constant acceleration on the way up

II. It has constant acceleration at the top of its path

III. It has constant acceleration as it moves downward.

• I only

• I and III

• III only

• All are correct

Which object would fall with greater acceleration in a vacuum - leaf or pebble?

• The leaf

• The pebble

• Difficult to determine without more information

• Both accelerate at the same rate

If you throw a ball straight up, what is its velocity at the highest point?

• 9.81 m/s²

• 0.0 m/s²

• 9.81 m/s

• 0.0 m/s

A ball is tossed upward and caught at the same position of throw. In the absence of air resistance, the speed of the ball when it is caught would be

• less than the speed it had when tossed upwards

• the same as the speed it had when tossed upwards

• more than the speed it had when tossed upwards

If air resistance is ignored, objects of different masses when dropped from rest

• fall with equal accelerations and with equal displacements

• fall with equal accelerations and with different displacements

• fall with different accelerations and with different displacements

• fall with different accelerations and with equal displacements

A hammer is dropped on Earth and the Moon. If gravitational pull on the Moon is about six times weaker than on Earth, where does a hammer fall faster?

• Moon

• Earth

• No difference

• Depends on the mass of the hammer

The state that exists when the only force acting on an object is gravity is called

• momentum

• acceleration

• inertia

• free fall

The standard acceleration due to gravity (or standard acceleration of free fall), is the nominal gravitational acceleration of an object in a vacuum near the surface of the Earth. It is defined by standard as:

• 9.8 m/s.

• 9.8 m.

• 9.8 m/s².

• 9.8 s.