Question

A football is kicked with a speed of 20 m/s at an angle of 37 degrees to the ground.

● (a) What is the maximum height that it reaches?

● (b) How far has it travelled horizontally when it reaches its maximum height?

● (c) What is the total time the football spends in the air?

Answer 1

at the maximum height final speed = 0

along vertical

vy^2 - voy^2 = 2*ay*dy

0 - (20*sin37)^2 = -2*9.8*h

height h = 7.4 m <<<======ANSWER

-------------

part(b)

from equation of motion

vy = voy + ay*t

0 = (20*sin37) - (9.8*t)

t = 1.23 s

x = vx*t = vo*cos3*t

x = 20*cos37*1.23

x = 19.65 m <<<<==========ANSWER

==================

part(c)

after falling on grond

y = 0

y = voy*T + (1/2)*ay*T^2

0 = (20*sin37*T) - ((1/2)*9.8*T^2)

T = 2.46 s <<<==========ANSWER