Find velocity of baseball at a height of 25 m.

Question

Hello,

I need help figuring out the following question: At t=0, a baseball is thrown upwards at 30 m/s from the ground. a) find its velocity at a height of 25 m; b) at what moments does its velocity equal to 15 m/s?

Much appreciated!

Answer 1

Vf 2 = Vi2 +2aH

Vf = ?

Vi = 30m/s A = -9.8, H= 25 m

Vf = 20.25m/s

Vf = 15m/s

t= ?

Vf = Vi +at

Vf =15 m/s , t=?, a= -9.8, Vi = 30 m/s

t= 15/9.8 Sec

= 1.53 S