Physics talk

[bogan]

This was accounted for.

on the topic of contact patchs

Did you know the area of the contact patch is irrelevant to the grip the vehicle has on the road?

In your head, or in the article somwhere between you quote and your conclusion?

Oh not this shit again, rubber in addition to be stretchy, is also adhesive. It's why drag cars get more grip from running larger contact patches. FFS man, pull that text book out of your arse and stretch your legs in the real world once in a while.

[Dave-]

In your head, or in the article somwhere between you quote and your conclusion?

Oh not this shit again, rubber in addition to be stretchy, is also adhesive. It's why drag cars get more grip from running larger contact patches. FFS man, pull that text book out of your arse and stretch your legs in the real world once in a while.

In the article, I cant quote too much from it otherwise I'll lose my access privileges.

Here's the equation for the frictional force, can you please point out where it says "area" or "A" or something squared?

[Drew]

In the article, I cant quote too much from it otherwise I'll lose my access privileges.

I think they'd be rapped with that result, if you are this beligerant on that site as well.

[bogan]

In the article, I cant quote too much from it otherwise I'll lose my access privileges.

Here's the equation for the frictional force, can you please point out where it says "area" or "A" or something squared?

Well with a lack of evidence, I'll assume you're jumping to an oversimplistic and erroneuous conclusion, as has been the trend thus far.

Adhesion is not part of friction. They are two different components that contribute to a tyre's grip.

[Drew]

Well with a lack of evidence, I'll assume you're jumping to an oversimplistic and erroneuous conclusion, as has been the trend thus far.

Adhesion is not part of friction. They are two different components that contribute to a tyre's grip.

Ooohhh, lets start discussing how friction can be detrimental to grip. Just for fun.

[onearmedbandit]

Did you know the area of the contact patch is irrelevant to the grip the vehicle has on the road?

Apparently it does though...

In terms of simple physics F = V mu... If you double the contact area, then the pressure will halve (per mm2) so the friction per mm2 will halve. However, you have twice the area of contact patch so that cancels out the halved pressure. The conclusion is that basic friction is independent of area, it only needs vertical load and a co-coefficient. You can do whatever you want with the area from a stiletto to a surfboard, the friction force will be the same.

However life is more complex than simple physics. The most obvious point is that tyre rubber is adhesive, so if you double the area you double the amount of adhesion (gross approximation). So wide tyres do have more grip than thin tyres.

The bit in bold I like the best.

http://www.f1technical.net/forum/vie...hp?f=6&t=12762

[bogan]

Ooohhh, lets start discussing how friction can be detrimental to grip. Just for fun.

Helmet friction is correlated with a tyre grip minimum?

Or the more serious answer of carcass flex and heat buildup pushing the tyre outside its designed limits.

[Drew]

Helmet friction is correlated with a tyre grip minimum?

Or the more serious answer of carcass flex and heat buildup pushing the tyre outside its designed limits.

Yeah, I was hoping it would go on for a bit, and then bring up overheating.

[bogan]

Yeah, I was hoping it would go on for a bit, and then bring up overheating.

My bad, it's tough at the top sometimes

[schrodingers cat]

You sure know a lot of theories Dave.
Best you stay at school and leave the real world to the rest of us.
All that education and no fucking idea :-)

[Ocean1]

Adhesion is not part of friction. They are two different components that contribute to a tyre's grip.

What causes adhesion?

[Dave-]

Apparently it does though...



The bit in bold I like the best.

http://www.f1technical.net/forum/vie...hp?f=6&t=12762

Going to need a better source than another forum OAB, seriously I could just cite myself on another forum and say "Oh look, I agree with myself!"

Have a read of this chaps, what do you reckon? I realise it's wikipeida, and I'm not saying it's true...
http://en.wikipedia.org/wiki/Tire_load_sensitivity

Race Car Vehicle Dynamics is in the EPS library, I'll have a browse Thursday arvo after my exam and cite from the genuine article rather than a wikipage (haha imagine that!)

Formula 1 Technology is out and due back on the 9th.

Come to think of it I should really update that wikipedia page on tyre deformation.....

[BMWST?]

Centrifugal force is what they teach you in high school cause your dumb undeveloped teenage brain can't comprehend that the direction of the force is towards the center of rotation.

And it works well for most people. If you want to know more most universities cover it in 100 level physics.

To conclude I think there's other things that attribute to the uncertainty in speedo reading, mechanical slip of the tyre, electronic pulses, the impedance of the inductor on the speedo increases with frequency, temperature, etc, on modern digital tachometers (the thing that shows you revolutions per minute) to save on costs they don't filter the signal, and it can get really saw-tooth shaped if you don't, when you do however you get a much more accurate representation, I know this cause I designed and built one at uni this year.

If you're really worried about it get a GPS, they're fail proof....except for when you cant connect to enough satellites

and the built in fudge factor by the us military which changes day to day

[BMWST?]

the phenomana of a tyre with low pressure having a smaller diameter than its correctly inflated brother is used by car manufactures to moniter tyre pressure.The wheel revolutions can be monitored with the abs hardware so if one wheel is spinning consistently faster than the others then the systems warns you that you have a flat tyre

[SMOKEU]

This thread is seriously anti lulz.