BASIC TRIGONOMETRY IN A CAR!!!
This special car draws a sine wave as it moves!
On y-axis, we have the sinθ component of the circle as shown in the upper figure, and on x-axis we have the movement of car which is rθ.
Therefore, the graph would be between (sinθ, rθ) which would be a sine curve.
Everyone has seen the above image of a unit circle, but when we showed this car to engineering students, they were not able to explain why the car draws a sine curve.