Question

(a) What force does a trampoline have to apply to Jennifer, a 45.0-kg gymnast, to accelerate her straight upward at 7.50 m/s2? (b) Does your answer to part (a) depend on whether Jennifer is in the process of landing on the trampoline (downward velocity) or being propelled off the trampoline (upward velocity)?

Answer 1

a) 778.95 N

b) No

Step-by-step explanation:

a) The trampoline will provide the force which is opposite to the force that Jennifer will provide by jumping on it

`F=m(a+g)\\\Rightarrow F=45* (7.5+9.81)\\\Rightarrow F=778.95\ N`

Force the trampoline has to apply is 778.95 N

b) Jennifer has to provide or the trampoline has to provide this amount of force in order to reach her desired height and acceleration. Her position in the process of the jump does not matter.