847 B
847 B
Torque and Rotational Dynamics
Summary
- Angular displacement is measured with
\Delta \theta=\theta-\theta_0 - Track angular displacement direction with clockwise counterclockwise sign convention
- Average angular velocity:
w_{avg}=\frac{\Delta\theta}{\Delta t} - Average angular acceleration:
a_{avg}=\frac{\Delta w}{\Delta t} - Rigid system holds shape, but different parts move at different speeds so you can't treat it as a single particle unless COM motion describes rotation well
- Slope of theta vs time shows angular velocity
- Slope of angular velocity vs time shows angular acceleration
- Integral of angular velocity vs time shows Delta theta
Angular vs. Linear Motion
Angular motion equations are similar to linear motion equations.
w=w_0+at
\theta=\theta_0+w_0t+\frac{1}{2}at^2
w^2=w^2_0+2a(\theta - \theta_0)