A wire fixed at the upper end stretches by length l by applying a force F. The work done in stretching is

Two wire of same material and same diameter have lengths in the ratio 2 : 5. They are stretched by same force. The ratio of work done in stretching them is

An elastic spring of unstretched length L and spring constant K is stretched by a small length x. It is further stretched by another small length y. the work done in second stretcing is

A steel wire of diameter 1 mm, and length 2 m is stretched by applying a force of 2.2 kg wt. the strain is

Three wires A,B and C are of the same length and cross section. They are each stretched by applying the same force to the ends. The wire A is stretched least and comes back to its original length when the stretching force is removed. The wire B is stretched more than A and also comes back to its original length when the stretching force is removed.The wire C is stretched most and remains stretched enen when stretching force is removed. The greatest Young's modulus of elasticity is possessed by the material of wire

An elastic spring of unstretched length L and force constant K is stretched by amoun t x .It is further stretched by another length y The work done in the second streaching is