A bucket filled with water weighing 20kg is raised from a well of depth 20m. If the linear density of the rope is 0.2 kg per meter, the amount of work done is ____ (in J). (g = 10 m/s2)

The work done will be the change in Gravitational potential energy of the (bucket+rope)

Change in potential energy of bucket = Mgh=$20\mathrm{x}\left(10\right)\mathrm{x}20=4000\mathrm{J}$

Change in potential energy of rope = $\mathrm{mg}\frac{\mathrm{h}}{2}=\mathrm{\lambda lg}.\frac{\mathrm{h}}{2}=0.2\mathrm{x}20\mathrm{x}10\mathrm{x}\frac{20}{2}=400\mathrm{J}$

So, total work done= 4400J