Question

Identify free fall situations from the following.

• A. A man landing with parachute
• B. An apple falling on moon
• C. A rocket propelling into space
• D. A block falling from a cliff

Answer 1

Answer: (B), (D)

A block falling from a cliff

A block falling from a cliff is in free fall under the gravitational force of the Earth and an apple falling on the Moon is under free fall due to the gravitational force of the Moon (since air resistance is negligible in both the cases). A parachute experiences drag force (resistance of air) and thus, another force except gravity acts on it and hence is not under free fall. An upthrust is used in a rocket during its propulsion due to the continuous expulsion of gases which again renders it not being under free fall.