Piyush Kumar Behera
Last Activity: 8 Years ago
I am only giving the procedure ,how to solve,because it is very difficult for me to type the latex and the equations.
In this question first of all calculate the angular velocity when the rod becomes horizontal by energy conservation.this can be done by :
decrease in potential energy of centre of mass =gain in rotational kinetic energy.
then the force on the pivot =forc eexerted by the pivot on the rod=mw2r.
so you get the result.