What is the principle of gear shifting?

[DelCharlotte]

The principle of gear shifting is achieved by changing the transmission gears. The tire drive shaft has gears for different gears. When the engine speed remains unchanged, gears of different sizes (different gears) are engaged with the engine. The circumferential speed obtained by the larger gear is less than that of the smaller gear. According to the knowledge of torque, in low gear, the gear is larger, and the engine drives a larger radius with a smaller radius, allowing the car to obtain greater driving force. In high gear, the engine drives a smaller radius, resulting in a faster circumferential speed, meaning the car moves faster but with less torque, i.e., less driving force. Therefore, gear shifting in a car is essentially changing the transmission gears.