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Torque on a shaft

  1. Jan 9, 2015 #1
    If a motor has a horsepower of 5hp and a gear box ratio of 10:1 does the hp through out the system remain 5? or does the gear box multiply the power?

    how does this affect the torque?
  2. jcsd
  3. Jan 9, 2015 #2

    Doug Huffman

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    Power is constant through a transmission and is the product of torque and angle rate.
  4. Jan 9, 2015 #3


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    ...minus the loss due to inefficiencies. Not to nitpick on you Doug Huffman, but considering the OP's question I think it is worthy of pointing out.
  5. Jan 10, 2015 #4
    power out = power in * efficiency
    torque out = torque in * (input speed / output speed) * efficiency
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