# Calculating the angle using angular acceleration

1. Apr 2, 2014

### james6008

Hi

I have calculated angular acceleration which changes with time. I also have a moment(torque) which also changes with time and a fixed moment of inertia. Is there an equation or a way for me to work out the change in angle with respect to time using this information? If not, what other information do I need?

2. Apr 3, 2014

### Staff: Mentor

If you know the angular acceleration as a function of time and you know the initial angular velocity at time zero, you can integrate with respect to time to get the angular velocity as a function of time. Then you can integrate again to get the change in angle with respect to time.

Chet

3. Apr 4, 2014

### james6008

The initial angular velocity will always be zero because the object starts moving from equilibrium.
So integrating angular acceleration gives me angular velocity. I thought integrating angular velocity will give me displacement/position or am I wrong thinking that?

4. Apr 4, 2014

### Staff: Mentor

Integrating angular velocity will give you angular displacement (aka change in angle).

Chet

5. Apr 4, 2014

### james6008

Perfect. Thanks for your help.