Question

If the body in is moving at 100 m/s on the earth’s surface, what will be its 

(i) kinetic energy 

(ii) total energy?

Answer 1

Data : m = 20 kg, u = 100 m/s .

(i) The kinetic energy of the body = \(\frac{1}{2}\) mv² = \(\frac{1}{2}\) × 20 kg × (100 m/s)² = 10⁵ J.

(ii) The total energy of the body = kinetic energy + potential energy = 10⁵ J + (- 1.2544 × 10⁹ J)

= (1 – 12544) × 10⁵ J = – 12543 × 10⁵ J

= – 1.2543 × 10⁹ J.