← Unit 7: Torque and Rotational Motion
Torque & Rotational Equilibrium
Torque is the rotational analog of force: τ = rFsinθ, and an object in rotational equilibrium has zero net torque.
Overview
Torque depends on both the force's magnitude and how far from the pivot (and at what angle) it's applied — a small force far from the axis can out-torque a large force close to it. For rotational equilibrium, the sum of clockwise torques must equal the sum of counterclockwise torques.
Practice Quiz
Question 1 of 1Score so far: 0/0
A figure skater spins with arms extended, then pulls her arms in. What happens to her angular velocity, assuming no external torque?