# Elastic potential energy $U_\text{elastic}$

Energy stored in a taught (elongated or compressed) spring, rubber band or other elastic material which via an elastic force wants to return to its original size.

$$U_\text{elastic}=\frac 12k\Delta L^2$$

$k$ is the spring constant and $\Delta L$ the difference in length (from relaxed length).

• Scalar property
• Symbol: $U_\text{elastic}$, $E_\text{pot,sp}$, $U_\text{spring}$
• SI-unit: Joule $\mathrm{[J]=[kg\cdot m^2/s^2]}$