Q22 (a)  A person trying to lose weight (dieter) lifts a 10 kg mass, one thousand times, to a height of 0.5 m each time. Assume that the potential energy lost each time she lowers the mass is dissipated.  How much work does she do against the gravitational force? 

Answers (1)
D Devendra Khairwa

The work done against the gravitational force is given by :

                                              =   Number of times the weight is lifted \times work done in 1 time.

                                             =\ 1000\times mgh

or                                          =\ 1000\times 10\times 9.8\times 0.5

or                                          =\ 49\ KJ