RRB Group-D Model Paper 13 with answers for online practice

• When a body of mass is raised from earth to a certain height, work must be work against gravity.

          Work done = Force × displacement

          We have

          Force= mass × acceleration

          Due to gravity

          F = mg

         Displacement equals a body's height when it is above ground level.

          So Work done = mg × h

          W = mgh

          Work done has the same units of energy that is Joules.