A football is kicked straight up into the air; it hits the ground 5.4 s later.

What was the greatest height reached by the ball? Assume it is
kicked from ground level.
With what speed did it leave the kicker’s foot? Answer to two sig. fig. and include the appropriate units.
Include all math(Algerba based) and why that formula was chosen.

Well, we have time, displacement, so we use the kinematic
equation
x=x(initial) + v(initial)t + .5at^2
0 = 0 + v(5.4) + (.5)(-9.8)(5.4)^2
5.4v = 142.884
v= 26.46 ==> 26 m/s as it leaves the kicker’s foot
Now we can use a different kinematic equation now that we know the
initial velocity.
V^2 = v(initial)^2 + 2ax because we know that velocity at max
height is 0 m/s, initial velocity is 26 m/s, and a is -9.8
m/s^2.
(0)^2 = (26.46)^2 + 2(-9.8)x
-19.6x = -700.1316
x= 35.721 ==> 36 meters

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