Solve this multiple-choice question and choose the correct option.

Concept/Approach Multiple jets increase flow (and power) at a given head by adding parallel jets spaced around the runner. To avoid interference, jets are typically spaced uniformly; practical design and bucket geometry generally limit the number. Answer reasoningIn practice, up to six jets are commonly employed on a Pelton runner without interference; more jets complicate spacing and often degrade performance. Final AnswerSix

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Impulse turbine (Pelton): Maximum practical number of jets without interference Assume standard bucket geometry and proper angular spacing to avoid jet interference at the runner. Choose the typical maximum number of jets used.

Difficulty: Easy

Two
Four
Six
Eight

Correct Answer: Six

Explanation:

Concept/Approach

Multiple jets increase flow (and power) at a given head by adding parallel jets spaced around the runner.
To avoid interference, jets are typically spaced uniformly; practical design and bucket geometry generally limit the number.

Answer reasoningIn practice, up to six jets are commonly employed on a Pelton runner without interference; more jets complicate spacing and often degrade performance.

Final AnswerSix

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