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Breast water wheel: operating principle Characterise how a breast water wheel develops torque relative to overshot and undershot wheels. Choose the correct description.

Difficulty: Easy

Runs purely by the impulse of water only
Runs purely by the weight of water only
Runs partly by the weight of water and partly by the impulse of water
Runs only by reaction of water jets

Correct Answer: Runs partly by the weight of water and partly by the impulse of water

Explanation:

Background

Water enters a breast wheel near the level of the wheel axis (breast height).

Operating principle
The wheel develops torque from both the weight of water contained in the buckets and the impulse of the incoming stream.

Final Answer
Partly by weight and partly by impulse.

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