 Now we can look at motion with constant acceleration. Now this video kind of assumes that you've watched a couple of my earlier videos. And these were ones in motion with one deep playlist. And they're the constant acceleration equations and constant acceleration strategy. So in those videos, we took a look at linear equations. So we were working with just the x direction. And we had a series of equations which represented that motion with constant acceleration. And amongst these equations, there was five variables, delta x, vi, vf, a and t. And each one of these equations had four of those variables. And you could use that to solve for some unknowns, but only if the acceleration is constant. Well now we're working with angular variables. So we have the angular displacement, the initial angular velocity, the final angular velocity, the angular acceleration and time. Time's not an angular variable, time is just time. So we still have five variables, but now we have their symbols for the angular versions, delta theta, omega i, omega f, alpha and t. So just like our linear equations, we can end up having a set of angular equations where each equation has four of these variables. And the equations are exactly the same as my linear equations, just replacing out the linear variables with the angular variables. And time still stays time. So this means we've got a set of equations anytime the angular acceleration remains constant. Now again, I had an earlier video that talked about this general strategy, so you can go watch that for a little more details. But if you have a problem where you know you have constant acceleration, make a list of that table of variables, fill in the ones you know, use the rule of three. In other words, I need to know three of the variables in order to find the other two unknowns. Select the right equation, the equation which has the three things you know and the one you want to find. Do your algebra, plug in your numbers, and then check your final answers to make sure they're reasonable. So we're following the exact same strategy and the same sort of equations here for angular acceleration that we did back with linear acceleration. So that's your motion with constant angular acceleration. We'll work quite a few example problems in class and on the homework.