When a tyre is spun at a high velocity, why do the spokes seem to be moving in the opposite direction?

Answer 1

Is it due to optical illusions? never was very sure, but I do know the effect to which you are referring . . .

Answer 2

If you are around a fluorescent light, it's actually flashing 60 times a second. Turn on a fan where the only light is coming from a fluorescent light. As you change speeds, the fan will appear to rotate backwards. If you are watching something on TV, the same thing will happen.

Answer 3

When you spin a tire, (fast) you can see the direction of the spokes change..why? its called aliasing, its a result of the rate at which your eyes take a full image in, think of it as a refresh rate, like the opposite of you monitor. Humans typically scan images at about 30 Hz. If you play any video games, or think of action movies, and when sometimes the "motion" looks like a slid show, this is because the frame rate you are view has fallen below 30 Hz and thus our eyes can pick up individual pictures that make up the "video".

How does this cause the spokes to appear to reverse? Well for the same reason that you can start seeing the individual frames of a video when it falls below 30 Hz, your eyes cannot refresh much faster 30Hz, and so imagine that something moves just faster then 30 Hz, say 45 Hz, if you can only see 30Hz then there will be some images that your eyes cannot detect because they are passing by too quickly.

Ok so the wheel is spinning, lets image a wheel with one spoke spinning clockwise, and your eyes picks up one image of the wheel and you see the spoke at 12 o'clock, if that wheel was spinning fast enough, so that your eyes didn't pickup the next image until the wheel spun all the way around and appeared at 11 o'clock, to you, you wouldn't know otherwise unless you knew the wheel was spinning clockwise, that it has infact moved from 12 o'clock to 11 o'clock, thus appearing to have moved counter clockwise. Since the wheel is spinning at a constant speed, the next time your eyes refresh, the wheel will have spun all the way around and already be at the 10 o'clock position, and thus you have seen 12 then 11, then 10...and it appears to be progressing in the counterclockwise direction.

try spinning a wheel as fast as you can, or even observing the wheels of a car near you on the freeway (assuming your not driving) you will see, given the car is changing speed, that this same effect causes the wheel to appear to rotate backwards, or even stand still, oh yeah it can't be one of those "dubs" with the free bearing decorative spinner spokes, which I assume came about because someone noticed the aliasing effect, and wanted to make a product that acted in a similar fashion.

How does this cause the spokes to appear to reverse? Well for the same reason that you can start seeing the individual frames of a video when it falls below 30 Hz, your eyes cannot refresh much faster 30Hz, and so imagine that something moves just faster then 30 Hz, say 45 Hz, if you can only only see 30Hz then there will be some images that your eyes cannot detect because they are passing by too quickly.

Ok so the wheel is spinning, lets image a wheel with one spoke spinning clockwise, and your eyes picks up one image of the wheel and you see the spoke at 12 o'clock, if that wheel was spinning fast enough, so that your eyes didn't pickup the next image until the wheel spun all the way around and appeared at 11 o'clock, to you, you wouldn't know otherwise unless you knew the wheel was spinning clockwise, that it has infact moved from 12 o'clock to 11 o'clock, thus appearing to have moved counter clockwise. Since the sheel is spinning at a constant speed, the next time your eyes refresh, the wheel will have spun all the way around and already be at the 10 o'clock position, and thus you have seen 12 then 11, then 10...and it appears to be progressing in the counterclockwise direction.

try spinning a wheel as fast as you can, or even opbserving the wheels of a car near you on teh freeway (assuming your not driving) you will see, given the car is changing speed, that this same effect causes the wheel to appear to rotate backwards, or even stand still, oh yeah it can't be one of those "dubs" witht eh free bearing decorative spinner spokes, which I assume came about because somone noticed the alliasing effect, and wanted to make a product that actied in a similar fashion.

Answer 4

It is an optical illution. Your brain can't take it all in, so it ignores the details, like the direction the spokes are spinning.

Answer 5

see when any object which is moving with great velocity,,,,, and if that object is not having uniform colour or shape,,,,,,, its reflects and assimilates light from some parts,,,,,,, hence its creates hallucination on our eyes,,,,,,, even human eyes cannot get the exact image of those two moves of same object which is moving is 1/10th second ,,,,,, hence sometimes we can see even different colours,,,,,,in same object,,,,,,, even this is seen in tyres,,,

Answer 6

Memory latency