You stretch a spring by a distance of 0.05 m. the spring has a spring constant of 125 n/m. when you release the spring, it snaps back. what is the kinetic energy of the spring as it reaches its natural length?

KE = 0.16 J

Explanation:

As we know that total energy is always remains conserved

so here we can say that initial potential energy stored in the spring is equal to the kinetic energy of the object when it comes to relaxed state

So here we have

here we know that

x = 0.05 m

now from above equation

so total potential energy here is same as the final kinetic energy which is 0.16 J

i think the answer is a, hope this : )