centripetal acceleration as a function of angular speed

In this lab, we were going to study about the angular velocity and angular acceleration.

As the picture show, we would rotate the plate and collect the period with timer. And then, we got following graph.

From the graph, we can see when period decreases, the acceleration is increasing.

Moreover, we know the equation:

w=2Pi/T

Therefore, when angular speed increases, the acceleration is increasing.

And we also found the graph about angular acceleration and angular velocity^2 gives a positive slope of 0.1493 as liner function. 

It shows that both of them are proportional to each other, and because it matters with radius of the turn table because a=r*w^2. a is acceleration and w is angular velocity, r is the slope of the graph.