Introduction:
Fuel is an essential component in an aeroplane as it powers the engines, allowing the aircraft to generate thrust and fly. There are several types of fuel used in various modes of transportation, and in the case of aeroplanes, the most commonly used fuel is kerosene.

Explanation:
Let's explore why pure kerosene is the correct answer for the fuel used in an aeroplane:

1. High energy content:
Kerosene possesses a high energy content, which is crucial for the efficient operation of an aircraft engine. This energy is released when the fuel is burned, and it is transformed into mechanical energy that propels the plane forward.

2. Combustion characteristics:
Kerosene exhibits specific combustion characteristics that are well-suited for aviation applications. It has a relatively high flashpoint, which means it requires a higher temperature to ignite compared to other fuels like petrol or diesel. This makes it safer to handle and store in aircraft fuel tanks.

3. Low freezing point:
Another advantage of kerosene is its low freezing point. At high altitudes, where temperatures can drop significantly, it is crucial for the fuel to remain in a liquid state. Kerosene's low freezing point ensures that it remains fluid even in extremely cold conditions, preventing any issues related to fuel flow or engine operation.

4. Availability and infrastructure:
Kerosene is widely available across the globe and is specifically produced for aviation purposes. This ensures a consistent supply of fuel for aircraft operations. Additionally, airports and aircraft are equipped with infrastructure and systems designed to handle kerosene safely and efficiently.

5. Engine design and compatibility:
Aircraft engines are specifically designed to run on kerosene. The combustion process, fuel injection systems, and overall engine design are optimized for the use of kerosene as the primary fuel. Using any other fuel, such as petrol or diesel, could lead to engine damage or inefficient operation.

Conclusion:
In conclusion, pure kerosene is the correct fuel used in aeroplanes. Its high energy content, combustion characteristics, low freezing point, availability, and compatibility with aircraft engines make it the ideal choice for powering aircraft and ensuring safe and efficient flight operations.