## How do engines make cars move?
The Basics of a Car Engine
A car engine is a machine that converts the chemical energy in gasoline into mechanical energy. This mechanical energy is then used to turn the wheels of the car and make it move.
The basic components of a car engine are:
* **Cylinders:** These are the chambers in which the gasoline is burned.
* **Pistons:** These are the moving parts that compress the gasoline and air mixture and then push it out of the cylinders.
* **Crankshaft:** This is the shaft that connects the pistons to the wheels.
* **Valves:** These are the openings that allow the gasoline and air mixture to enter the cylinders and the exhaust gases to exit the cylinders.
The Four-Stroke Cycle
The four-stroke cycle is the process by which a car engine converts the chemical energy in gasoline into mechanical energy. The four strokes are:
1. **Intake stroke:** The intake valve opens and the piston moves down, drawing the gasoline and air mixture into the cylinder.
2. **Compression stroke:** The intake valve closes and the piston moves up, compressing the gasoline and air mixture.
3. **Power stroke:** The spark plug ignites the gasoline and air mixture, causing it to burn. The burning gases expand and push the piston down, turning the crankshaft.
4. **Exhaust stroke:** The exhaust valve opens and the piston moves up, pushing the exhaust gases out of the cylinder.
The Transmission
The transmission is a gearbox that connects the engine to the wheels. The transmission allows the driver to change gears, which changes the speed and torque of the wheels.
The Differential
The differential is a gearbox that splits the power from the transmission and sends it to the two wheels on the same axle. The differential allows the wheels to turn at different speeds when the car is cornering.
Putting it all Together
When you press the gas pedal, the engine starts to burn more gasoline and air. This causes the pistons to move faster and turn the crankshaft faster. The faster the crankshaft turns, the faster the wheels turn.
The transmission allows you to change gears, which changes the speed and torque of the wheels. The differential allows the wheels to turn at different speeds when the car is cornering.
All of these components work together to make your car move.
