Question

A football is kicked at ground level with a speed of 18.0 m/s at an angle of 35.0 degrees to the horizontal. How much later does it hit the ground?

Answer 1

V o = 18 m/s,
v o y = v o * sin 35° = 18 * 0.5736 = 10.32437 m/s
y = v o y·  t - 1/2 g t²
0 m = 10.32437 m/s t - 1/2 · 9.81 m/s² · t²  /: t
4.905 t = 10.32437
t = 10.32437 : 4.905
t = 2.1 s
Answer:
A ball will hit the ground after 2.1 seconds.