Under the ruler faster than the ruler

u need to do books on tape

JOH TICHY SHOWS SOME WEIRD VIDEOS

It is anti-clockwise.

You are all partially right, even coolaun. ALL the radius(circumference) ratios play a part in making this device move faster than the ruler. Some ratios work better some worse. Just think in terms of your transmission and tire size. Some ratios will not even work because sufficient force might not be transferred to move the device. See the videos "It works" then "8 to 40" and last "40 to 40". Perhaps you'll figure it out.

nadahere, mathematical analysis shows that the size of the blue wheel plays no part in the relation between speed of cart and speed of ruler. This is easily confirmed in an empirical test. If the radius of the ends of the cotton reels is b, the radius of the part of the cotton reels where the blue wheel touches them is a, Vr is the speed of the ruler and Vc that of the cart, then:

Vc = Vr(b/(b-a))

The cart goes faster when the two values are close.

I made a general statement regarding ratios of gears/wheels their velocities, power transfer and non/functionality. I should have clarified that if the center wheel was small the ruler might not be able to transfer enough force to make the device work. Ergo, even the center wheel contributes to making this device move faster than the ruler.

But surely in that case, when b=a the velocity of the cart goes to infinity, which is impossible.

Yes, indeed: when b = a the cart doesn't work! Up to a certain point, the closer a is to b, the faster the cart goes in relation to the ruler (you can see this if you look carefully at panoik's videos). But this can't go on indefinitely: when a is very close to b, the ruler starts to slip. You can see what happens when b is exactly equal to a in avian6's video, "Experiments with a three-roller cart": when the ruler is moved, it just skids over the wheel.

Haha, it's almost like a small scale case of special relativity. Assume a << b otherwise the laws of physics break down!

:p

its sooooo true this guys voice is so relaxing! idk y?!