The staples inside a stapler are kept in place by a spring with a relaxed length of 0.115 m. If the spring constant is 51.0 N/m, how much elastic potential energy is stored in the spring when its length is 0.150 m?

To find the elastic potential energy stored in the spring, we can use the formula:

Elastic Potential Energy = 1/2 * k * Δx^2

Where:
k = Spring constant
Δx = Change in length of the spring

First, let's calculate the change in length of the spring (Δx):
Δx = Final length - Relaxed length
= 0.150 m - 0.115 m
= 0.035 m

Now, we can substitute the values into the formula:

Elastic Potential Energy = 1/2 * 51.0 N/m * (0.035 m)^2
= 1/2 * 51.0 N/m * 0.001225 m^2
= 0.031125 Joules

Therefore, the elastic potential energy stored in the spring when its length is 0.150 m is approximately 0.031125 Joules.