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This is not true. It can indeed be seen in real life. In fact, my entire family was travelling north on a highway when we were passing an 18 wheeler (a truck). One of my kids became really excited and asked outloud why the front wheels of that truck were moving backwards! We all looked and sure enough the illusion of the wheels moving backwards was very strong! The truck had very shiney rims with many, many nuts/bolts to hold the tire onto the hub. It was a bright day and the light reflecting off the rims was pretty intense. However, the nuts looked as if they were moving in the opposite direction and thus the wheel looked like it was rotating backwards.


Our brain has no fixed 'frame rate' and our eyes have definitely no shutter. Nevertheless, contrary to what I said you can indeed observe the backwards rotating effect in real life. The prerequisite is that something external must then act as a shutter.

The most usual effect is a stroboscobe. When lighting a rotating wheel with a stroboscobe that flashes faster than the rotation speed, you see it slowly turn backwards. If the stroboscobe flashes slower, you can see the wheel slowly turning forward. If you ever have adjusted the distributor arm of a car engine you know the effect.

In the case of your truck, what your kids were seeing was a double reflection. Sun light was reflected from two different wheels into their eyes, and both wheels had a slightly different rotation speed (due to a different diameter). So you probably saw one wheel slowly turning backwards and another one forward. Maybe the other wheel was not directly visible so the backwards effect was predominant.

You can use that effect to ask your kids small riddles, for instance "Which wheel has a newer tire, the backwards rotating or the other one?"