Question

A girl on a backyard trampoline bounces straight upward with an initial speed of 4.5m/s. What is the girl's velocity when she returns to the trampoline?

(I would like a step-by-step explanation so I can understand the answer please. Thank You)

Answer 1

Answer: Final speed,Vf= -4.5m/s

It is the same speed but in opposite direction,coming down against gravity.

Step-by-step explanation:

Calculating distance,d= (Vf^2-Vo^2)/2g

d=(0-4.5^2)/(2×9.8)

d= -20.25/19.6

d= -0.053m

Vf^2=Vo^2 + 2gd

Vf= Sqrt(0 +2×9.8(×-0.053))

Vf=V=-4.5m/s