Question

A body of 1 kilograms is how to fall freely from a height of 25 m calculate its kinetic energy potential energy and Total energy at the instance it is at a height of 4 m from the Earth when g
equal to 10 M per second square

Answer 1

Given,
u=40 m/s
For maximum height,v=0 m/s
Using relation,
v2−u2=2gh0−402=2×(−10)×hh=80 cm1−Kinetic energy is equal to potential energy at h'=h/2=80/2=40 cm2−Potential energy of body of mass 10kg is given byP.E=mgh=10×10×80=8000 J
 

Answer 2

The velocity of that instant moment

V^2=2as

...... =2.10.(25-4)

..... =420

V=√420

The kinetic energy

Ev=1/2mv^2=1/2*420=210j

The total potential energy is

Ep= m.h.g=1.10.4=40j

Total energy is=210+40=250j