Answer:
13.5 J
Explanation:
mass of ball, m = 3 kg
maximum height, h = 2.8 m
initial speed, u = 8 m/ s
Angle of projection, θ
use the formula of maximum height
[tex]H = \frac{u^{2}Sin^{2}\theta }{2g}[/tex]
[tex]2.8 = \frac{8^{2}Sin^{2}\theta }{2\times 9.8}[/tex]
Sin θ = 0.926
θ = 67.8°
The velocity at maximum height is u Cosθ = 8 Cos 67.8 = 3 m/s
So, kinetic energy at maximum height
[tex]K=\frac{1}{2}mv^{2}[/tex]
K = 0.5 x 3 x 3 x 3
K = 13.5 J
