Sequence of energy conversions in a coal-fired power station

Steps:

• Burning coal (stage 4, implied in flow chart) produces thermal energy to generate steam (stage 6).
• The boiler absorbs and becomes hot (stage 3) to sustain the steam process.
• High-pressure steam drives the turbine, which turns the generator (stage 1).
• The generator's motion induces electrical energy via electromagnetic induction (stage 5).

Why A is correct:

• It matches the thermodynamic flow: steam production (6) heats the boiler (3), mechanical rotation (1) enables induction (5) per Faraday's law of electromagnetic induction.

Why the others are wrong:

• B: Places turbine (1) before boiler heating (3), skipping necessary heat transfer for steam pressure.
• C: Omits steam production (6) and misorders induction (5) before turbine (1), violating mechanical-to-electrical sequence.
• D: Positions induction (5) before turbine (1), ignoring that generator motion is required for induction.

Final answer: A