NTSE Stage 2 SAT 2015 Question Paper

A small spherical ball of mass ‘m’ is used as the bob of a pendulum. The work done by the force of tension on its displacement is ${\mathrm{W}}_1$ The same ball is made to roll on a frictionless table. The work done by the force of normal reaction is ${\mathrm{W}}_2$ . Again the same ball is given a positive charge ‘g’ and made to travel with a velocity ‘v’ in a megnetic field B. The work done by the force experienced by the charge ball is ${\mathrm{W}}_3$ . If the displacements in each case are the same, we have