1. A rod of length l and radius r is joined to a rod of length l/2 and radius r/2 of same material. The free end of small rod is fixed to a rigid base and the free end of larger rod is given a twist of A degrees. The twist angle at the joint will be (ans-8A/9)
2.A uniform wire of length l and radius r is twisted by angle A. if modulus of rigidity of wire is B then elastic potential energy stored in wire is?(ans-pie*B*r^4*A^2/4l)
3.Two wires A and B are of same length and of same material having radii r1 and r2 respectively. Their one end is fixed with a rigid support and at the other end equal twisting couple is applied. Then ratio of the angle of twist at the end of A and the angle of twist at the end B will be? ans-r1^2/r2^2