KVPY SX SB Exam 2013 Question Paper

A wheel of radius R with an axle of radius $\frac{\mathit{R}}{2}$ is shown in the figure and is free to rotate about a frictionless axis through its centre and perpendicular to the page. Three forces {F, F, 2F) are exerted tangentially to the respective rims as shown in the figure. The magnitude of the net torque acting on the system is nearly