[" 0.A spring when compressed by "4cm" has "],[2J" energy stored in it.The force required "],[" to extend it by "8cm" will be "]

A spring when compressed by 4 cm has 2 J energy stored in it. The force requried to extend it by 8 cm will be

When a spring is compresssed by 3 cm the potential energy stored in it is U. When it is compressed further by 3cm, the increase in potential energy is

If a spring extends by x and on loading, energy stored by the spring is

A spring when stretched up to 2cm has potential energy U .If it is stretched up to 8cm ,potential energy will be : ?

A spring with spring constaant k when compressed by 1 cm the PE stored is U. If it is further compressed by 3 cm, then change in its PE is