question_answer

A spring of unstretched length l has a mass m with one end fixed to a rigid support. Assuming spring to be made of a uniform wire, the kinetic energy possessed by it if its free end is pulled with uniform velocity v is: [JEE ONLINE 12-04-2014]

A) \[\frac{1}{2}m{{v}^{2}}\]

B) \[m{{v}^{2}}\]

C) \[\frac{1}{3}m{{v}^{2}}\]

D) \[\frac{1}{6}m{{v}^{2}}\]