When an object moves in a circular orbit (of radius R), the acceleration has two components, tangential and radial. The angular speed is defined as \omega=d\theta/dt, and angular acceleration defined as \alpha=d^2\theta/dt^2 (\theta is the angle that measures the movement of the position vector); the two components are then generally:

a_{tan} = R\alpha,

a_{rad} = R\omega^2 = \frac{v^2}{R}.

In many cases we work with uniform circular motion, in this case a_{tan}=0.

credit: Prof. Walter Lewin of MIT (course 8.01, Physics I: Classical Mechanics, fall 1999).

Topics covered in this lecture:

Circular Motion – Centrifuges Moving – Reference Frames – Perceived Gravity

Advertisement