Question

The fluid in the petrol engine (S.I) during compression contains
1. Fuel only
2. Fuel or Air
3. Air only
4. Mixture of air and fuel

Answer 1

Correct Answer - Option 4 : Mixture of air and fuel

Explanation:

SI Engine:

• Petrol is used as fuel.
• A petrol engine draws a mixture of petrol and air during the suction stroke.
• A mixture of petrol and air is compressed during the compression stroke.
• The pressure at the end of the compression is about 10 kg/cm2
• The charge (i.e. petrol and air mixture) is ignited with the help of a spark plug.
• A  carburettor is used to atomize, vaporize and meter the correct amount of fuel according to the requirement.
• A petrol engine has a compression ratio approximately from 6 to 10.
•  The combustion of fuel takes place approximately at a constant volume. In other words, it works on the Otto cycle.
• Less vibration, and hence, smooth running.
• Engine weight is less.
• It emits carbon monoxide. (CO)