2.3 Acceleration of free fall

In Newtonian physics, ________________ is any motion of a body where gravity is the only force acting upon it.

• kinematics

• free fall

• mechanics

• velocity

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.

Which of the following graphs best represents free fall motion?

• 
• 
• 
• 

Free fall takes into consideration the frictional force of air resistance.

• True

• False

Heavier objects free fall faster than lighter objects. [Ignore air resistance]

• True

• False

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.

What happens to the velocity of a ball as it is dropped off a cliff? 

[Ignore air resistance]

• It decreases at a uniform rate 
• It increases at a uniform rate 
• It is constant 
• It increases at a non-uniform rate

A textbook is dropped from a second floor window and falls to the ground. What happens to the velocity as the book falls to the ground

• the velocity increases

• the velocity decreases

• the velocity remain constant

A textbook is dropped from a second floor window and falls to the ground. What happens to the acceleration as the book falls to the ground? [Ignore air resistance.]

• the acceleration increases

• the acceleration decreases

• the acceleration remains constant

Which is constant for a freely falling object? [Ignore air resistance]

• displacment

• acceleration

• velocity

• speed

Answer explanation

Only acceleration is constant in free fall on Earth, at 9.81m/s²