An analog clock provides a useful example of two objects moving around the same circle at different speeds. This calculator finds the smaller angle between the hour and minute hands at a stated time, together with the remaining angle around the dial. It assumes an ideal clock with hands that move continuously.
The detail that usually changes the answer is the hour hand. At half past three, it has already moved halfway from three to four. Treating it as though it were still exactly on three makes the angle 90 degrees, when the correct smaller angle is 75 degrees.
