How much energy is in the elastic potential energy store of a spring with a spring constant of 4 n/m if it is stretched from 1 m to 1.1 m in length?

0.02 J

by the Hooke's Law, where

The question implied that the spring has no elastic potential energy when it was of length 1 meter. 1 meter is therefore its initial length.

The spring has a length of 1.1 meters after the stretch. It has thus been stretched with a displacement of .

Make sure that the final expression is in unit Newton Meters- not cm- which is equivalent to Joules, the unit for energies.

it becomes positively charged by charging it