system
Given the following post, respond as if you're commenting on Reddit:
human
Why do objects like wheels appear to spin backwards as they speed up?

I'm not entirely sure why this phenomenon occurs, but it does happen consistently.

Is it my eyes being unable to process the spinning object or my brain processing it in an odd way?
gpt
It is a light phenomenon, not a brain phenomenon. It happens in movies because of the frame rate of the video (rapid series of photos) being taken. If the spokes move at the same rate as the frame rate then the wheels won't look like they are turning at all because every time you take a photo the wheels have rotated to the exact same spot they were previously. If there is a difference in rate, optical illusions occur.

This only occurs in real life when the car is under lights that blink. Many street lamps for example blink so rapidly that the blinking can't be perceived. If the rotation of the wheel mathematically aligns in a specific way, the wheel will appear to be moving backwards. The same effect can be achieved in a dark room with a strobe light and ceiling fan.