Let a and b be the distances from the center of the bearing to the edges of the wheel A and the axle B. If the input force F A is applied to the edge of the wheel A and the force F B at the edge of the axle B is the output, then the ratio of the velocities of points A and B is given by a/b, so the ratio of the output force to the input force, or mechanical advantage, is given by

The number of axles in a car depends on the type of vehicle, as Car From Japan states. In most cases, cars have two axles to rotate the wheels. Larger vehicles that carry more passengers and have more wheels may have more axles. Roller Bearings – A bearing collar containing needle roller bearings, often the most common and well used bearings. Most suitable for medium duty applications, making the wheel easier to move.After watching the film, you could work with pupils to explore the different parts of a vehicle and what function each one serves. A pulley is a simple machine used to change the direction of a force. Think of raising a flag or lifting a heavy stone. To lift a stone up into its place on a pyramid, one would have to exert a force that pulls it up. By using a pulley made from a grooved wheel and rope, one can pull down on the rope, capitalizing on the force of gravity, to lift the stone up. Even more valuable, a system of several pulleys can be used together to reduce the force needed to lift an object. wheel and axle: A simple machine that reduces the friction of moving by rolling. A wheel is a disk designed to turn around an axle passed through the center of the wheel. An axle is a supporting cylinder on which a wheel or a set of wheels revolves. A M A = F out F in = η ⋅ R a d i u s wheel R a d i u s axle {\displaystyle \mathrm {AMA} ={F_{\text{out}} \over F_{\text{in}}}=\eta \cdot {\mathrm {Radius} _{\text{wheel}} \over \mathrm {Radius} _{\text{axle}}}}

where [math]R[/math] is the radius of the wheel, and [math]r[/math] is the radius of the axle, shown in Figure 2. Attema, P. A. J.; Los-Weijns, Ma; Pers, N. D. Maring-Van der (December 2006). "Bronocice, Flintbek, Uruk, JEbel Aruda and Arslantepe: The Earliest Evidence Of Wheeled Vehicles In Europe And The Near East". Palaeohistoria. University of Groningen. 47/48: 10–28 (11). ISBN 9789077922187. Aleksander Gasser (March 2003). "World's Oldest Wheel Found in Slovenia". Government Communication Office of the Republic of Slovenia . Retrieved 19 August 2010.Some simple vehicle designs, such as leisure go-karts, may have a single driven wheel where the drive axle is a split axle with only one of the two shafts driven by the engine, or else have both wheels connected to one shaft without a differential (kart racing). However, other go-karts have two rear drive wheels too. with holes cut through for an axle. Solid wheels like this evolved into lighter and faster semisolid wheels, But, there’s something else that every car, van, lorry and train needs to allow it to move, and that’s an axle.