Achieve Your Highest Grade

Home | Premium Plan | Students | Teachers | Intro to A Level | Video Index | Past Papers | Shop

#### Rotational Dynamics

A little intro with a bit of text

### 1. Rotational Dynamics Playlist Intro

Rotational dynamics builds on your work on circular motion, but this time we consider rotating objects that speed up and slow down as well. Follow me on my journey through this topic.

### 2. Rotational Kinetic Energy

An object that is spinning has no overall velocity, yet it still stores energy in the form of rotational kinetic energy. In this video I start the journey exploring rotational dynamics by deriving the equation for this energy and also introduce the idea of moment of inertia.

### 3. Moment of Inertia

The moment of inertia is a measure of the way in which the mass of a body is distributed around its axis of rotation. Although you don’t have to remember the expressions of I for different shapes it is worth seeing how it varies for different shapes.

### 4. Angular Acceleration

Developing your previous work on circular motion and angular velocity as the rate of change of angular displacement, we can now develop this idea by looking at the rate of change of angular velocity and how this leads onto angular acceleration.

### 5. Torque

Apply a force at a distance from an axis and it will undergo an angular acceleration. You can also calculate the torque applied if you know its moment of inertia and the angular acceleration. Find out more in this video.

### 6. Work and Power

This video looks at the work done by a torque and also the power of a rotating object and how we can derive these two simple equations.

### 7. Rotational Equations

There’s a lot in this video including how to derive the four ‘suvat’ like equations for rotational motion. You don’t have to recall these, however, you should be able to follow the process.

### 8. Angular Momentum

The angular momentum, L, is the product of an objects linear momentum and its perpendicular distance from an axis of rotation. In this video I show you the expression for the angular moment of a rotating object and also how momentum is conserved – provided a torque is not applied to the system.

### 9. Translations vs Rotational

By this stage in your education you know a huge amount about F=ma, suvat equations and so on. These are analogous to the equations for rotational motion which I explore further in this video.