Adult And Children Bicycles Manufacturers introduce a common sense of bicycle use:
1. Knowledge of stability

The reason why the bicycle does not tip over during driving is mainly due to the application of physics principles. When we ride a bicycle, we give the bicycle a force in the forward direction, so that the wheels can be turned, and the wheels can be kept in a balanced state. After adjusting by turning the handlebars, the bicycle can move forward. Once stopped, the balance is lost and the bicycle will fall.

2. Knowledge of friction

1) Friction during starting and driving

When the bicycle starts or runs, the rear wheel rotates counterclockwise under the drive of the chain, and the contact point between the tire and the ground tends to move backward relative to the ground. Therefore, the ground exerts a forward friction force on the rear wheel, which is the driving force for the bicycle to move forward. Under the action of this force, the bicycle has a tendency to move forward as a whole, and the front tire of the bicycle has a tendency to move forward at the place where it touches the ground, and the ground generates a backward friction force against the front wheel. Under the action of this frictional force, the front wheel rotates in the same direction as the rear wheel, and the bicycle moves forward.

Therefore, people also refer to the rear wheel as the driving wheel and the front wheel as the driven wheel. When it rains or snows, the friction on the ground becomes weaker, and the bicycle is easy to fall over, which is usually called skidding. This is the reason. The uneven pattern on the tires of bicycles is to increases friction.

2) Friction during braking

Friction is not only related to the starting of the bicycle but also very important to the braking of the bicycle. If the braking performance is not good, the safety of the cyclist cannot be guaranteed. A person pinches the brake lever to make the brake cable drive the brake block to close to the tire, creating friction, which slows the bicycle and finally stops.

The magnitude of friction depends on the magnitude of the pressure and the roughness of the contact surface. The new bicycle and the old bicycle, at the same speed, use approximately the same force to pinch the brake lever. The new bicycle brakes quickly. The reason is that the brake pads and tires of the old bicycle are worn smooth and the friction generated is very small. In addition, the handlebars, pedals, etc. of the bicycle are made with uneven patterns. This also increases the friction by increasing the roughness of the contact surface.

3. Shock absorption system

The bicycle is equipped with shock absorbers. A total of 5 parts of the bicycle have been shock-absorbing: the tripod, saddle, front and front, and rear tires. The tripod, saddle, and front of the bicycle are damped by springs, and the body is dumped by tires.

When the bicycle vibrates, the entire body has deformability, which increases the time when a person falls in contact with the body, reduces the force, and improves comfort.

For example, if a person jumps from a height to the concrete floor, his feet will feel pain. If a soft cushion is laid on the ground, the person jumps down again. Even at the same height, the feeling will not be so intense. The shock absorption not only makes the rider feel comfortable but also reduces the wear and tear of the bicycle.

4. Pressure knowledge

1) The load capacity is engraved on the bicycle tire. If the vehicle is too heavy, the tire will be crushed by too much 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 difficult for people to feel fatigued when riding.

3) In the summer, the tires tend to blow out under strong sunlight. This is because the gas in the tire absorbs heat under the sunlight, the temperature rises, the heat expands, and the pressure increases, so the tires are easy to explode.

4) The function of the valve core: The valve core on the inflatable inner tube acts as a one-way valve, allowing only gas to enter, not allowing gas to leak out, facilitating air intake, and ensuring the sealing of the inflated inner tube.

5. Knowledge of simple machinery

1) Leverage knowledge

A. The lever that controls the steering of the front wheel: The handlebar of the bicycle is a labor-saving lever. People can turn the front wheel of the bicycle with a small amount of force to control the direction of the bicycle and the balance of the bicycle.

B. The lever that controls the brake: The brake lever on the handlebar is a labor-saving lever, and people can press the brake on the steel rim of the wheel with a small amount of force.

2) Wheel and axle knowledge

A. Pedals and faceplate gears on the bottom axis: compose a labor-saving axle (the pedal radius is greater than the faceplate gear radius).

B. Bicycle handlebar and front fork shaft: form a labor-saving wheel shaft (the turning radius of the handlebar is greater than that of the front fork shaft).

C. Gears and rear wheels on the rear axle: compose a laborious axle (the radius of the gear is smaller than the radius of the rear wheel).

6. Knowledge application of work and mechanical energy

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

2) The mutual transformation of kinetic energy and gravitational potential energy.

For example, before riding a bike uphill, people often have to step up a few times to get up more easily. Here is the transformation of kinetic energy into potential energy. While riding downhill without pedaling, the speed is getting faster and faster. This is the conversion of potential energy into kinetic energy.

7. Application of the law of inertia

For a fast-moving bicycle, if the front wheel is suddenly braked, why does the rear wheel jump up? This is because the front wheels suddenly stop moving due to resistance, but the people on the car and the rear wheels do not receive resistance. According to the law of inertia, the people and the rear wheels must keep moving forward, so the rear wheels will jump up. Remember that when driving downhill or at high speed, the front brake of the bicycle cannot be braked alone, otherwise, a rollover accident may occur!

8. Optical knowledge

The red taillights on bicycles can't light up by themselves, but they can remind the car driver to pay attention at night. Because the taillights of bicycles are composed of many honeycomb-shaped "compartments", and each "compartment" is composed of three reflective surfaces about 90 degrees.

In this way, at night, when the light of the car behind hits the taillight of the bicycle, it will produce reflected light. Because the red is eye-catching, it can attract the attention of the driver. When a person faces the car bell, he will see his own image. This is because the shape of the bell cover is equivalent to a convex mirror, and what a person sees is an upright and reduced virtual image due to reflection.