Enter the torque applied, length of the shaft, polar moment of inertia, and shear modulus into the calculator to determine the angle of twist.

## Angle of Twist Formula

The following formula can be used to calculate the angle of twist of a solid shaft.

a = ( T * L )/( J * G)

- Where a is the angle of twist (radians)
- T is the torque applied (N*m)
- L is the length (m)
- J is the polar moment of inertia
- G is the shear modulus (N/m^2)

## Angle of Twist Definition

An angle of twist is defined as the measure of the amount of twist in radians an object undergoes when subjected to a torque.

## Angle of Twist Example

How to calculate an angle of twist?

**First, determine the torque applied.**Measure the total torque.

**Next, determine the length.**Measure the length of the rod.

**Next, determine the polar moment of inertia.**Calculate the moment of inertia of the rod.

**Next, determine the shear modulus.**Calculate the shear modulus of the rod.

**Finally, calculate the angle of twist.**Calculate the angle of twist using the equation above.

## FAQ

**What is angle of twist?**

An angle of twist the measure of the amount of twist an object, typically a rod, undergoes when a torque is applied in to the ends of the rod.

**What is the polar moment of inertia?**

The polar moment of inertia is the measure of the object’s resistance to twisting.