Question

A 52 kg child on a swing is travelling at 6 m/s . What is his gravitational potential energy if he has 1000 J of the mechanical energy?

Answer 1

Answer:

The correct answer is "64 J".

Explanation:

The given values are:

Mass,

m = 52 kg

Velocity,

v = 6 m/s

Mechanical energy,

= 1000 J

Now,

The gravitational potential energy will be:

⇒ $P.E=1000-\frac{1}{2}mv^2$

           $=1000-\frac{1}{2}\times 52\times (6)^2$

           $=1000-26\times 36$

           $=1000-936$

           $=64 \ J$