Moments, torque, and angular momentum

Everything you've learned about motion, forces, energy, and momentum can be reused to analyze rotating objects. There are some differences, though. Here, you'll learn about rotational motion, moments, torque, and angular momentum.

Torque, moments, and angular momentum

Until this tutorial, we have been completely ignoring that things rotate. In this tutorial, we'll explore why they rotate and how they do it. It will leave your head spinning (no, it won't, but seemed like a fun thing to say given the subject matter).
Introduction to torque
An introduction to torque
Introduction to moments
Moments (part 2)
2 more moment problems.
Finding torque for angled forces
In this video David explains how to determine the torque exerted by a non perpendicular force.
Rotational version of Newton's second law
In this video David explains moment of inertia and the rotational version of Newton's second law and shows how to solve an example problem.
More on moment of inertia
In this video David explains more about what moment of inertia means, as well as giving the moments of inertia for commonly shaped objects.
Rotational kinetic energy
In this video David explains what rotational kinetic energy is and how to calculate it.
Rolling without slipping problems
In this video David explains how to solve problems where an object rolls without slipping.
Angular momentum
Constant angular momentum when no net torque
Just like how linear momentum is constant when there's no net force, angular momentum is constant where there's no net torque
Angular momentum of an extended object
In this video David derives and shows how to use the formula for the angular momentum of an extended object.
Ball hits rod angular momentum example
In this video David explains how a mass can have angular momentum even if it is traveling along a straight line. Then David shows how to solve the conservation of angular momentum problem where a ball hits a rod which can rotate.
Cross product and torque
The cross product and the direction of torque