A rod of mass m and length / is made to stand at an angle of 60^@ with the vertical. Potential energy of the rod in this position is

A rod of mass m and length / is made to stand at an angle of 60^@ with

1.	A rod of mass m and length / is made to stand at an angle of 60^@ with the vertical. Potential energy of the rod in this position is
Answer» `MGL` `(mgl)/2` `(mgl)/3` `(mgl)/4` Solution :For any UNIFORM rod, the mass is supposed to be concentrated at its centre. Height of the mass from ground is `h = (l//2) sin 30^@` POTENTIAL energy of the rod `= MGH xx m xx g xx l/2 sin 30^@` `= m xx g xx l/2 xx 1/2 = (mgl)/(4)`.