Question

Find the work done in the following:a) work done in changing the velocity 20m/s to 30m/s if the mass of object is 2kg . b) find the work done of a object of mass 3kg from a height of 5m to 15m. c)work done is moving a object of 0.5kg by 10m with an acceleration of 0.1 m/s square.d)work done in delivering power of 350 wates in 20 seconds

Answer 1

a).
we have given, v=30m/s
                         u=20m/s
                         m=2kg
                         work= 1/2m(vv-uu)
                                 =1/2.2.(900-400)
                          work=500J