A hollow copper cylinder is of inner radius 4 cm outer radius 5 cm. Now hollow portion is completely filled with suitable copper wires. Find percentage change in its electric resistance.

A hollow cylinder with inner radius R . Outer radius 2R mass M is rolling with speed of it's axis v . What is its kinetic energy ? .

A hollow cylinder with inner radius R . Outer radius 2R mass M is rolling with speed of it's axis v . What is its kinetic energy ? .

A hollow cylinder of inner radius 3 cm and outer radius 5 cm and a solid cylinder of radius 2 cm are subjected to the same force. If they are made of same material and of same length, then the ratio of their elongations is

A copper cylindrical tube has inner radius a and outer radius b. The resistivity is p. The resistance of . the cylinder between the two ends is

A copper cylindrical tube has inner radius a and outer radius b. The resistivity is p. The resistance of . the cylinder between the two ends is

A copper wire of resistivetly rho is stretched to make it 5% longer. Find the % change in its resistance.