Question

what should a free-body diagram look like for a skydiver that is still speeding up as he falls?
A. there is an arrow up for air resistance and an arrow down for gravity. the arrow up is shorter than the arrow down.
B. there is only an arrow down for gravity.
C. there is an arrow up for air resistance and an arrow down for gravity. the arrows are the same length.
D. there is an arrow up for for air resistance and an arrow down for gravity. the arrow up is longer than the arrow down.

Answer 1

if the sky diver is accelerating downwards, this means that the overall net force is downwards, then newton's second law

if the sky diver's speed it constant, this means that the net force of the skydiver is zero

assuming that the net force is downwards or a negative number, net force means the sum of all forces along the same axis, so in the case of gravity and air resistance, gravity must be greater than air resistance in order to cancel it out and still have some force left over in order to still have some acceleration