Answer: Force applied by trampoline = 778.5 N
Note: The question is incomplete.
The complete question is : What force does a trampoline have to apply to a 45.0 kg gymnast to accelerate her straight up at 7.50 m/s^2? note that the answer is independent of the velocity of the gymnast. She can be moving either up or down or be stationary.
Explanation:
The total required the trampoline by the trampoline = net force accelerating the gymnast upwards + force of gravity on her.
= (m * a) + (m * g)
= m ( a + g)
= 45 kg ( 7.50 * 9.80) m/s²
Force applied by trampoline = 778.5 N