When a 500-N parachutist opens his chute and experiences 800 N of air resistance,the net force on him is
A)300 N downward.
B)500 N downward.
C)800 N downward.
D)300 N upward.
E)500 N upward.

Question

Quizplus · Accepted Answer

When the 500-N parachutist opens his chute, he experiences two forces: his weight of 500 N pulling him downwards and the air resistance of 800 N pushing upwards. Since these forces are in opposite directions, we need to subtract the smaller force from the larger force to find the net force. 
800 N - 500 N = 300 N. 
Therefore, the net force on the parachutist is 300 N upwards, which is the same direction as the air resistance force. However, since the question is asking for the direction of the net force on the parachutist, the answer is 300 N downwards, which is the opposite direction to the net force. The correct answer is D.

When a 500-N Parachutist Opens His Chute and Experiences 800