Enter the torsion spring constant and angle of twist into the calculator to determine the torsion bar spring energy.

Torsion Bar Spring Energy Formula

The following equation is used to calculate the Torsion Bar Spring Energy.

U = 1/2 * k * a^2

  • Where U is the torsion spring energy storage (joules)
  • k is the torsion spring constant (N-m/radian)
  • a is the angle of twist (radians)

To calculate the torsion bar spring energy, multiply the torsion spring constant by the angle of twist squared, then divide by 2.

What is a Torsion Bar Spring Energy?


A torsion bar spring energy measures the potential energy store with a spiral/torsional spring that has been twisted by a certain angle.

How to Calculate Torsion Bar Spring Energy?

Example Problem:

The following example outlines the steps and information needed to calculate Torsion Bar Spring Energy.

First, determine the torsion spring constant. In this example, with the help of the calculator linked above, the spring constant is found to be 50 N-m/radian.

Next, determine the angle of the twist. In this case, the angle of twist is measured to be 3 radians.

Finally, calculate the torsion bar spring energy using the formula above:

U = 1/2 * k * a

U = 1/2 * 50*3^2

U = 225 Newton-meters=Joules