A soccer player kicks the ball toward a goal that is 16.8 m in front of him. The ball leaves his foot at a speed of 16.0 m/s and an angle of 28.08 above the ground. Find the speed of the ball when the goalie catches it in front of the net.

Answer: final speed V = 14.71m/s

Explanation:

To determine the final speed

Given;

Distance of travel d = 16.8 m

Initial speed u = 16.0m/s

Angle to the horizontal a = 28.08°

Vx = ucosa = horizontal component of speed

Vy = usina = vertical component of speed

Time of travel t = d/Vx = 16.8m/16cos28.08 = 1.19s

The final vertical and horizontal component of speed

Vx = 16cos28.08 = 14.12m/s

Vy = Uy - gt = 16sin28.08 - 9.8 (1.9) = - 4.13m/s

Final speed

V = √ (Vx^2 + Vy^2)

V = √ (14.12^2 + (-4.13) ^2)

V = 14.71m/s