Definition check — internal vs. external combustion: Engines in which the chemical energy of the fuel is released by combustion taking place inside the engine cylinder itself are called internal combustion engines. State whether this statement is correct.

Introduction / Context:
This question distinguishes internal combustion (IC) engines from external combustion (EC) prime movers. In IC engines, fuel burns inside the working cylinder, directly raising the pressure and temperature of the working fluid that pushes the piston or drives a turbine. In EC systems such as steam power plants, fuel burns outside the engine, and heat is transferred to a separate working fluid (water/steam).

Given Data / Assumptions:

• The statement claims: if combustion occurs inside the cylinder, the engine is an internal combustion engine.
• Typical IC examples: petrol (spark-ignition) engines, diesel (compression-ignition) engines, gas turbines.
• Typical EC examples: steam engines and steam turbines where fuel burns in a boiler/furnace.

Concept / Approach:
The defining criterion is the location of heat release relative to the working fluid. If the working fluid is the combustion products themselves and combustion occurs within the power-producing component, the engine is IC. If combustion heats a separate fluid in a heat exchanger (boiler), it is EC. Therefore, the statement is accurate by definition.

Step-by-Step Solution:

Verification / Alternative check:
Consider a diesel engine: air is compressed in the cylinder, fuel is injected and burns in the same space; the expanding gases perform work on the piston. This satisfies the IC definition. Conversely, a steam engine’s piston is driven by steam generated in a boiler where fuel burns externally, so it is EC.

Why Other Options Are Wrong:

• False: Contradicts the standard definition.
• True only for petrol/diesel: Both petrol and diesel are IC; limiting the definition to one subtype is incorrect.

Common Pitfalls:
Confusing the presence of a carburettor or injector with the IC/EC classification; the classification depends on where combustion occurs, not on the fuel metering device.

Final Answer:
True