Question

A particle of mass 1kg is moving with a velocity of 20ms^-1 then its kinetic energy is ____

(a) 200 J

(b) 200 kgm^2s^-1

(c) 200 kgm^-1s^-2

(d) 200 kgm^-1s^-1

I had been asked this question in a job interview.

Enquiry is from Kinetic Energy topic in chapter Work, Energy and Power of Physics – Class 11

Answer 1

Right choice is (a) 200 J

The explanation is: Kinetic energy of a particle is given by 0.5*m*v^2 i.e. 0.5*1*20^2 = 200 J. Joules can also be written as kgm^-2s^-2.