A particle of mass 100 gm thrown vertically upwards with a speed of  5 m/s.  The work done by the force of gravity during the time, the particle goes up is

     $Work done by gravity =-Ve$
   $$\begin{gathered} from work energy theorem, \\ work done = change in KE \\ initial velocity = 5m/s \\ final velocity = 0 \\ mass m =\frac{100}{1000}kg \\ W=K.E_{final}-K{E}_{initial} \\ W=\text{\hspace{0.17em}0-\hspace{0.17em}\hspace{0.17em}}\frac{1}{2}m{v}^2 \\ W=-\hspace{0.17em}\frac{1}{2}\frac{100}{1000}{\text{\hspace{0.17em}5}}^2 \\ W=-1.25 joule \\ Here gravity is opposite to the displacement and hence the work done by gravity is equal to negative of ptential energy \\ when the body moves up. \end{gathered}$$