Okay, so in this video we're going to derive the formula v is equal to or omega, that is the linear velocity of an object in circular motion is equal to the radius of the circle times the angular velocity omega. So to do this we're going to start with the definition for a radian which is teta, the angle is equal to s over or s being the arc length and or being the radius. We can then get this and divide both sides by t so that would be teta over t is equal to s over or times t. Now we know that omega, the angular velocity is equal to the angle teta over time, that's the definition of angular velocity. And we also know that v velocity is equal to distance over time. So I can substitute in omega here for teta over t, so that gives me omega on that side. And then s over t will now become v, so that's v over or v over or. And then I just need to multiply across by or and rearrange to get v is equal to or omega as required.