Question

The ratio of brake horse power indication horse power is called -
1. Mechanical efficiency
2. Overall efficiency
3. Indicating thermal efficiency
4. Brake thermal efficiency

Answer 1

Correct Answer - Option 1 : Mechanical efficiency

Explanation:

Indicated Horse Power and Brake Horse Power

• The power actually generated by the engine or generator is the indicated horse power which is indicated on the plate.
• The Brake horse power is the power available to do useful work. B.H.P is always less than I.H.P. due to losses to overcome frictional resistance.
• \(\therefore \rm Mechanical~efficiency,~{\eta _m} = \dfrac{{BP}}{{IP}} × 100\%\)
• Work done by a force = Magnitude of the force × distance moved by the body
• \(\rm Power = \dfrac{Total~ work~ done}{ total ~time ~taken}\)
• \(\rm Efficiency = \dfrac{Power ~output}{Power~ input} \times 100\%\)