Question

a girl on a backyard trampoline bounces straight upward with an initial velocity with 4.5 m/s what is the girls velocity when she returns to the trampoline

Answer 1

-9.8 m/s because she is basically falling and -9.8 is gravity

Answer 2

Answer:

Final speed,Vf= -4.5m/s

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

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