Question

A heavy block is suspended from a vertical spring.

The elastic potential energy is stored in the spring is 4 J.

What is the spring constant if the elongation of the spring is 10 cm?

Answer 1

The elastic potential energy is

$$E=\frac 12kx^2,\\\space\\ k=\frac{2E}{x^2}=800\text{ N/m}.$$