Question

A particle of mass 200g is thrown vertically upwards with a speed of 10ms^-1, the work done by force of gravity while the particle goes up is given by _____

(a) 0.5J

(b) 5J

(c) 10J

(d) 15J

This question was addressed to me in an interview for job.

I'd like to ask this question from Kinetic Energy topic in portion Work, Energy and Power of Physics – Class 11

Answer 1

Correct option is (c) 10J

Easy explanation: The maximum height attained by particle is given by u^2/(2*g). So total work done would be gain in potential energy i.e. m*g*h = m*g*(u^2/(2*g))= (200/1000)*10*(10^2/20) = 10.