A football is kicked 66.6 meters. If the ball is in the air 5.39 s, with what initial velocity was it kicked?

1 answer

Tr = Tf = 5.39/2 = 2.695 s.
Tr = Rise time.
Tf = Fall time.

Y = Yo + gt.
Y = 0 + 9.8*2.695 = 26.4 m/s = Final velocity when falling = Initial velocity
(Yo)when rising. Y=Ver. componenttg of velocity.

Range = Xo*(Tr+Tf) = 66.6 m.
Xo*(5.39) = 66.6
Xo = 12.36 m/s. = Hor. component of
initial velocity.

tanA = Yo/Xo = 26.4/12.36 = 2.13592
A = 64.9o.
Vo=Xo/cosA=12.36/cos64.9=29.2 m/[email protected]
= Initial velocity.