A 640-N Acrobat Falls 5

Multiple Choice

A 640-N acrobat falls 5.0 m from rest into a net.The net tosses him back up with the same speed he had just before he hit the net.The average upward force exerted on him by the net during this collision is:

A) 32 N
B) 64 N
C) 320 N
D) 640 N
E) impossible to determine from given data