Question

9 m ki height se ek ball ko giraya jata hain to 2 sec k baad iski potential energy and kinetic energy me ratio btae

Answer 1

Given height=9m

let height be h=9m

    velocity of the ball be vm/s

    initial velocity of the ball be u=0m/s

acceleration due to Earth's gravity=10 m/s^2

By 1$1^{st}$ equation of motion,

v=u+gt

v=0+10(2)

v=20

Kinetic Energy(KE)=$\frac{1}{2}mv^2$

                       =$\frac{1}{2}m\times20^2$

                       =200m

Potential Energy(PE)=$m\times g\times h$

                           =90m

Ratio=$=\frac{PE}{KE}\\\\ = \frac{90}{200}\\\\ =\frac{9}{20}\\\\=0.45$

Ans-0.45