3． Application of pressure knowledge

(1) The load capacity is engraved on the bicycle tire. If the vehicle is overweight, the tire will be crushed due to excessive pressure.

(2) The seat cushion is saddle-shaped, which can increase the contact area between the seat cushion and the human body to reduce the pressure on the buttocks, making it easier for people to feel fatigue while riding a bicycle.

4． Application of simple mechanical knowledge

The brake handle and connecting rod in the bicycle braking system are a labor-saving lever that can increase the pulling force on the brake pads. In order to save effort or distance, bicycles also use axles: pedal plates and sprockets; rear wheels and flywheels, faucets and rotating shafts, etc.

5. Knowledge and application of work and mechanical energy

(1) According to the principle of work: saving effort must waste distance. This is why people often ride "S-shaped" routes when going uphill.

(2) Mutual conversion of kinetic energy and gravitational potential energy.

For example, before riding a bicycle uphill, people often have to pedal a few times to make it easier to go up. Here, kinetic energy is converted into potential energy. When riding a bicycle downhill, the speed becomes faster and faster without pedaling. This is the conversion of potential energy into kinetic energy.

6. Application of the law of inertia

Why does the rear wheel of a fast-moving bicycle jump up if the front wheel is suddenly braked? This is because the front wheel suddenly stops moving due to resistance, but the person and the rear wheel on the car do not receive resistance. According to the law of inertia, the person and the rear wheel must continue to move forward, so the rear wheel will jump up.

Remember that when going downhill or driving at high speed, you cannot brake with the front brake of the bicycle alone, otherwise a rollover accident may occur!