Important convention: Angles are always measured anticlockwise from the positive x-axis.
Drag the angle slider along to see how the sine graph is generated. Consider how this follows on from the first applet. Why is it useful to use the unit circle (radius 1)?
What is the amplitude of the sine graph? How can you tell by looking at the graph/unit circle?
What is the period of the sine graph? How can you tell by looking at the graph/unit circle?