Efficiency Physics Example 3

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Example 3

medium

A coal power plant burns fuel releasing

1{,}000{,}000 \text{ J}

and generates

350{,}000 \text{ J}

of electrical energy. What is the efficiency?

Solution

1
Apply the efficiency formula.
2
$\eta = \frac{350{,}000}{1{,}000{,}000} \times 100\% = 35\%$

Answer

\eta = 35\%

Thermal power plants typically have efficiencies of 30-40%. Most energy is lost as waste heat. This is why improving efficiency is crucial for energy conservation.

About Efficiency

The ratio of useful output energy (or power) to total input energy, expressed as a percentage — always less than 100% due to energy losses.

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