1. Chemical Energy: Petrol is a fuel containing stored chemical energy. This energy is released when the petrol is burned (combusted).
2. Combustion: Inside the car's engine (typically an internal combustion engine or ICE), the petrol is mixed with air and ignited by a spark plug. This controlled explosion rapidly expands the gases.
3. Mechanical Energy: The expanding gases push pistons within the engine cylinders. This linear motion of the pistons is converted into rotational motion by a crankshaft.
4. Transmission of Power: The rotational motion from the crankshaft is transmitted to the wheels through a transmission (gearbox). The transmission modifies the speed and torque (rotational force) to suit different driving conditions.
5. Motion: The rotational motion of the wheels, driven by the engine through the transmission, pushes against the road surface. This creates friction, resulting in the car moving forward.
In short, the chemical energy in petrol is converted into mechanical energy which turns the wheels, causing the car to move.
