Question

A long spring when stretched by x has a potential energy V. On increasing the stretching to 'nx' the potential energy stored in the spring will be

Answer 1

Potential energy of a spring,If spring is stretched by a length'x'U=12kx2If spring is stretched by a length x'U'=12kx'2or UU'=x2x'2UU'=0.0220.082=0.00040.0064=0.0625Or U'=10.0625×U=16 U
Thus, if spring is stretched by 8 cm (0.08 m), the potential energy will become 16 U.