MHT CET202311 May 2023Evening ShiftPhysicsLaws of MotionActual
In a conical pendulum the bob of mass ' m ' moves in a horizontal circle of radius ' r ' with uniform speed ' V '. The string of length ' L ' describes a cone of semi vertical angle ' '. The centripetal force acting on the bob is ( g = acceleration due to gravity)
Options
- Amgr L ^2- r ^2
- Bmgr ( L ^2- r ^2 )
- CL ^2- r ^2 mgL
- DmgL L ^2- r ^2
Correct answer
A. mgr L ^2- r ^2
Step-by-step solution
aligned & T = mg & = r L & = L ^2- r ^2 ~L aligned aligned T & = mg = mgL L ^2- r ^2 mr ^2 & = T T r L & = m ^2 ...( = r L ) ^2 & = g L ^2- r ^2 aligned The centripetal force is F = mgr L ^2- r ^2