|
|
|
|
|
| Author |
Message |
![[Post New]](/templates/default/images/icon_minipost_new.gif) 17 Dec 2006 01:03:11 IST
|
|
|
Hiiiii..
cud someone plz explain rolling friction andhow exactly it is caused???
|
i luv goiit......thanx every1 |
|
|
|
17 Dec 2006 06:56:29 IST
|
|
|
Hey actually in pure or ideal rolling no friction acts. As then the point of contact with the surface would be temporarily at rest. But actually slipping occurs (forward or backward) and hence there would be friction as the relative motion would be present.
|
They say ITZ NOT THE APTITUDE BUT THE ATTITUDE WHICH DECIDES U R ALTITUDE . THEN WHY M I NOT AT THE TOP IN THIS SITE? LIFE IS JUST NOT FAIR. |
this reply: 0 points
(with 0 
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
17 Dec 2006 22:25:00 IST
|
|
|
Rolling resistance, sometimes called rolling friction, is the resistance that occurs when an object (e.g a wheel or tire) rolls. It is much smaller than sliding friction except for special cases like ice skating. It is caused by the deformation of the wheel or tire or the deformation of the ground. It depends very much on the material of the wheel or tire and the sort of ground. For example, rubber will give a bigger rolling friction than steel. Also, sand on the ground will give more rolling friction than concrete. A vehicle rolling will gradually slow down due to rolling friction, but a train with steel wheels running on steel rails will roll much further than a car or truck with rubber tires running on pavement, even when differences in mass and momentum are accounted for. Factors contributing towards rolling friction Several factors affect the magnitude of rolling friction a tire generates: - Material - Tires with higher sulfur content tend to have a lower rolling friction. This is one strategy that most hybrid car vendors use to improve fuel efficiency.
- Dimensions - rolling friction is related to the flex of sidewalls and the contact area of the tire.
- Extent of inflation - Lower pressure in tires results in more flexing of sidewalls and higher rolling friction.
- Over inflating tires (such a bicycle tires) may not lower the overall rolling resistance as the tire may skip and hop over the road surface. Traction is sacrificed, and overall rolling friction may not be reduced as the wheel rotational speed changes and slippage increases.
- Tread thickness has much to do with rolling resistance. The thicker the tread, the higher the rolling resistance. Thus, the "fastest" bicycle tires have very little tread and heavy duty trucks get the best fuel economy as the tire tread wears out.
- Smaller wheels, all else being equal, have higher rolling resistance than larger wheels
|
The Scientist does not study nature because it is useful; he studies it because he delights in it, & he delights in it because it is beautiful. If nature were not beautiful, it would not be worth knowing, life would not be worth living. Ofcourse I do not here speak of that beauty that strikes the senses, the beauty of qualities & appearances; not that I undervalue such beauty, far from it, but it has nothing to do with science; I mean that profounder beauty which comes from the harmoniuos order of the parts, & which a pure intelligence can grasp. |
this reply: 0 points
(with 0
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
|
|
|
|
|
|
|
Moderation Team
![[Up]](/templates/default/images/icon_up.gif "[Up]"){kind=icon}
