A 2 m long weightless spring having a force constant 25 N/m hangs from ceiling. At its lower end is suspended a mass of 1 kg. If it is pulled down by 10 cm and released then the kinetic energy when the spring has moved 5 cm up is:
1
0.125 Joule
2
0.0312 Joule
3
0.0624 Joule
4
0.0938 Joule