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The efficiency of an impulse turbine is maximum when (where Vb = Blade speed, V = Absolute velocity of steam entering the blade and α = Nozzle angle)

The efficiency of an impulse turbine is maximum when (where Vb = Blade speed, V = Absolute velocity of steam entering the blade and α = Nozzle angle) Correct Answer V<sub>b</sub> = 0.5 V cosα

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