physica-free fall question

2007-10-27 9:32 pm

A boy jump and his feet are 0.5m above the ground.
(a) find the hang-time of the boy
(b) find the jumping speed of the boy.

回答 (1)

2007-10-27 10:27 pm

✔ 最佳答案

V=0
U=X
A=-10ms-2
S=0.5m
T=?

要計b先。
b) V^2=U^2+2as
0=U^2=2(-10)(0.5)
10=u^2
U=-3.16

a)
v=u+at
0=-3.16+-10t
t=0.136ms-1

參考: me

👍 0 👎 0