Rolling friction Definition and 59 Threads

Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the motion when a body (such as a ball, tire, or wheel) rolls on a surface. It is mainly caused by non-elastic effects; that is, not all the energy needed for deformation (or movement) of the wheel, roadbed, etc., is recovered when the pressure is removed. Two forms of this are hysteresis losses (see below), and permanent (plastic) deformation of the object or the surface (e.g. soil). Note that the slippage between the wheel and the surface also results in energy dissipation. Although some researchers have included this term in rolling resistance, some suggest that this dissipation term should be treated separately from rolling resistance because it is due to the applied torque to the wheel and the resultant slip between the wheel and ground, which is called slip loss or slip resistance. In addition, only the so-called slip resistance involves friction, therefore the name "rolling friction" is to an extent a misnomer.
In analogy with sliding friction, rolling resistance is often expressed as a coefficient times the normal force. This coefficient of rolling resistance is generally much smaller than the coefficient of sliding friction.Any coasting wheeled vehicle will gradually slow down due to rolling resistance including that of the bearings, but a train car with steel wheels running on steel rails will roll farther than a bus of the same mass with rubber tires running on tarmac. Factors that contribute to rolling resistance are the (amount of) deformation of the wheels, the deformation of the roadbed surface, and movement below the surface. Additional contributing factors include wheel diameter, load on wheel, surface adhesion, sliding, and relative micro-sliding between the surfaces of contact. The losses due to hysteresis also depend strongly on the material properties of the wheel or tire and the surface. For example, a rubber tire will have higher rolling resistance on a paved road than a steel railroad wheel on a steel rail. Also, sand on the ground will give more rolling resistance than concrete. Sole rolling resistance factor is not dependent on speed.

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    Rear Wheel Driven Car Rolling Friction

    if a rear wheel driven car is accelerated i think... 1. on rear wheels friction is forward 2 on front wheels it is backward my questions- 1.wats d direction of rolling friction on the car as a whole?(is dis question correct?) 2.which wheel will have greater magnitude of friction??
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    Force due to wind and rolling friction on van

    Homework Statement The graph shows the speed as a function of time for a minivan, coasting on neutral along a straight, level road, loaded with windsurfing equipment and towing a boat. The total mass is 2500 kg, weight= 5512lbs. Find the size of the force due to wind and rolling friction when...
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    Rolling Friction: Coefficient for Tire on Concrete

    HI everyone who reads this,, i need to know a simple thing, but i coudln't figure it bymyself.. what i need to know is coefficient of rolling friction say,, a tire,(not vehicle,, just a small tire) on a concrete road what would that be ? does anyone who knows?? it doesn't have to be...
  4. M

    Rolling Friction of hollow cylinder

    Consider a hollow cylinder rolling down an inclined plane, without slipping. I know that the rolling friction does no work on the point which is in contact with the cylinder, since that point must be at rest since we have rolling without slipping, but isn't the ENTIRE BODY still moving, so the...
  5. K

    Find the Coffiecient of Rolling Friction

    Information given: Two bicycle tires are set rolling with the same initial speed of 3.60 m/s along a long, straight road, and the distance each travels before its speed is reduced by half is measured. One tire is inflated to a pressure of 40 {\rm psi} and goes a distance of 18.1 m; the other...
  6. K

    Rolling Friction and Bicycle Tires, Mastering physics problem.

    Information given: Two bicycle tires are set rolling with the same initial speed of 3.60 m/s along a long, straight road, and the distance each travels before its speed is reduced by half is measured. One tire is inflated to a pressure of 40 {\rm psi} and goes a distance of 18.1 m; the other...
  7. S

    Deriving the Coefficient of Rolling Friction for a Cart on an Incline

    Hello. I need some help with the following problem. There is a cart on an incline and a pulley with a suspended block. Assuming that (the force of friction)= (mu)(N) symbolically show that the coefficient of rolling friction for the car moving down the incline plane with a constant...
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    Rolling Friction and Bicycle Tires

    my teacher Never went over this in class. ever. please help, thanks Two bicycle tires are set rolling with the same initial speed of 3.70 m/s along a long, straight road, and the distance each travels before its speed is reduced by half is measured. One tire is inflated to a pressure of 40 psi...
  9. M

    Calculating Final Position of Billiard Ball with Rolling Friction

    My problem involves rolling a billiard ball with an initial x velocity of 2.4ms and an initial y velocity of 0.7ms. The rolling friction is 0.1 and I have to work out the final resting position of the ball. There is no sliding friction involved. I have to break this into 0.1seconds and...
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