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Pelton wheel unit power: compute from given head and output A Pelton wheel develops 1750 kW under a head of 100 m, runs at 200 r.p.m., and discharges 2500 L/s. Find the <em>unit power</em> of the wheel (power at unit head for a similar turbine). Choose the correct value.

Difficulty: Easy

0.25 kW
0.75 kW
1.75 kW
3.75 kW

Correct Answer: 1.75 kW

Explanation:

Given data

P = 1750 kW
H = 100 m
Unit power definition: P_u = P / H^3/2

Step-by-step calculation
H^3/2 = 100^3/2 = 100 × √100 = 100 × 10 = 1000 P_u = 1750 / 1000 = 1.75 kW

Verification
Unit quantities remove head effect; values of order 1–5 kW are typical for such data.

Final Answer
1.75 kW

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