Question

2. In a car engine, an electrical spark from the spark plug ignites the fuel-air mixture in the piston. The explosion and heat cause the air in the cylinder to expand, pushing the piston down.

Answer 1

The energy process in a car engine involves:

• chemical energy, thermal energy, mechanical energy, thermal energy,

The chemical energy stored in the fuel-air mixture is transformed into thermal energy during the combustion process. When the spark plug generates an electrical spark, it ignites the fuel-air mixture in the piston.

This ignition leads to a rapid chemical reaction, breaking down the hydrocarbons in the fuel and releasing a amount of heat energy. This thermal energy causes the air in the cylinder to heat up and expand rapidly which creates a high-pressure environment within the cylinder.

Next, this thermal energy is used to perform mechanical work. As the expanding hot gases push against the piston, they exert a force on it, causing it to move downward. This motion of the piston is what drives the crankshaft and ultimately powers the car's wheels.

The mechanical energy generated from the piston's movement is then transmitted through the various components of the engine to propel the vehicle forward.

Answer 2

First, the electrical spark of the car engine is the initial energy that is electrical energy, then the explosion and heat form the thermal energy, then, it produces sound energy and stills getting thermal energy to finally converts to kinetic energy to move the car. The order is:

`\text{Electrical}\to Thermal\to\text{Sound}\to Thermal\to Kinetic`