When a parachutist jumps from an airplane, he eventually reaches a constant speed, called the terminal velocity. This means that

A) gravity is no longer acting on the parachutist.
B) the force of air resistance is equal to the weight of the parachutist.
C) the force of air resistance is equal to zero.
D) the acceleration is equal to g.

Question

When a parachutist jumps from an airplane, he eventually reaches a constant speed, called the terminal velocity. This means that

A) gravity is no longer acting on the parachutist. 
B) the force of air resistance is equal to the weight of the parachutist. 
C) the force of air resistance is equal to zero. 
D) the acceleration is equal to g.

anonymous · Answer

"B)the force of air resistance is equal to the weight of the parachutist. ". It is the definition of the terminal velocity : the body will not move faster, because the weight (gravitationnal pull) is equal to the air drag.

stormfire1 · Answer

B is correct...

A is wrong because he's still falling
C is wrong because the only time air resistance would be zero would be if he was falling in a perfect vacuum
D is wrong because once you reach terminal velocity you are no longer accelerating

anonymous · Answer

A free-falling object achieves its terminal velocity when the downward force of gravity (Fg) equals the upward force of drag (Fd) caused by the fluid it is moving through - here it is air. This causes the net force on the object to be zero, resulting in a zero acceleration.

so B)