Bicycle accessories talk about friction on bicycles:
1 Why should bicycle tires have uneven patterns? The magnitude of friction is related to two factors: the size of the pressure and the roughness of the contact surface. The greater the pressure, the greater the friction; the rougher the contact surface, the greater the friction. The bicycle tire has a concave and convex pattern, which increases the friction by increasing the roughness between the bicycle and the ground, and the purpose is to prevent the bicycle from slipping.
2 After the brakes, why can the bicycle stop? When braking, the friction between the brake skin and the rim will hinder the rotation of the rear wheel. The greater the pressure on the hand, the greater the pressure on the rim of the brake shoe, the greater the friction generated, and the slower the rear wheel rotates. If it is completely braked, the friction between the rear wheel and the ground becomes the sliding friction (originally rolling friction, direction forward), and the direction is backward, which hinders the movement of the bicycle, so it stops.
3 Where are the bicycles with steel balls? Why are the steel balls in the bicycle's front axle, middle axle, rear axle, handlebar rotation, pedal rotation, etc. People riding bicycles always want to be relaxed, flexible and labor-saving. The use of rolling instead of sliding can greatly reduce the friction. Therefore, to install the steel ball in the place where the bicycle rotates, we can often add lubricating oil to make the contact surfaces away from each other, so that the friction can be made smaller.