, A uniform rod of mass m and length / is held inclined at an angle of 600 with the vertical. What will-be potential energy of the rod in this position ?
m g I
m g I/2
m g I/3
m g I /4
See fig. (12). Let the center of gravity of the rod be at a
height ft. From figure,
h=OCsin30∘=(l/2)sin30∘=l/4 P.E. =mgh=mgl/4