Answer:
B .
Explanation:
Elastic potential energy stored in a spring is given by;
E=1/2*k*{Δl}² where
k= spring constant
Δl = change is length of spring
if k is different the energy stored in the system is different. This is true also in the case where Δl is different.
For a parallel system, springs help each other to carry the weight. The stiffness doubles up to mean ;
k parallel =2k
and
Δl parallel = 1/2 Δl
so;
E in one spring = 1/2*k*{Δl}²----------{a}
Using {a} this in the parallel system;
E parallel = 1/2 * 2k * {1/2Δl}²
= 1/2 * 2* k* 1/4 *{Δl}²
= 1/2 E in one spring
Answer : Ep / 2
