Question

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)

a.

Vb = 0.5 V cos α

b.

Vb = V cos α

c.

Vb = 0.5 V2 cos α

d.

Vb = V2 cosα

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Answer: (a).Vb = 0.5 V cos α

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Q. 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)

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