Question

A body of mass 10 kg accelerates and its velocity increases from 10 m/s to 20 m/s. Calculate the total work done.

Answer 1

=> MASS OF BODY = 10 Kg

=> INITIAL VELOCITY ( U ) = 10 m/s

=> FINAL VELOCITY ( V ) = 20 m/s

--> NOW , THE WORK DONE ON THE BODY WILL BE THE CHANGE IN ITS KINETIC ENERGY.

=> K.E = mv^2

2

=>WORK DONE = CHANGE IN KINETIC ENERGY

=> WORK DONE = mv^2 - mu^2

2 2

= m ( v^2 - u^2 )

2

--> ON PUTTING VALUES ,

= 10 ( 20^2 - 10^2 )

2

= 5 ( 400 - 100)

= 5 × 300

= 1500 joules