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Homework Help: Definition of what 1 horsepower is

  1. Jun 26, 2009 #1
    I have an equation in my study guide that looks like this:

    a = F/m = P/v/m = (47 horsepower * 746 W/hp) / (1400kg) (14m/s) = 1.82 m/s^2

    My question is, how does my book come up with 746 W/hp? I know why all of the other factors are there, but what numbers were used to get the 746 W/hp. If someone could let me know I would really appreciate it. Thanks.
  2. jcsd
  3. Jun 26, 2009 #2


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    Re: Power

    It's the definition of what 1 horsepower is. 1 horsepower=746 watts. So 746 W/hp=1. You basically just look it up.
  4. Jun 26, 2009 #3
    Re: Power

    Hey, thanks. I just read that in my book, I appreciate your help.
  5. Jun 26, 2009 #4


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    Re: Power

    1 Hp is the power necessary to lift a 75 kg load to a 1 meter height in one second (standard definition). The energy in such a system is E=75kg*1m*g and the power is E/1sec so one Hp is just 75kg*9.8m/s2 Watts.
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