Define one H.P

Replies

• 

  Sharfudeen Mohamed Ibrahim

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  I think this pic speaks.
  
  source: Horsepower
• 

  NAVATHE SACHIN

  sorry sharfudeen i know about that pic but i did not understand.suppose,I give you an example : specific heat of water is 4.18 J/Kg.k . so ,here the value indicates 4.18 joules of energy is required in order to raise the temperature of 1 kg of water by one degree celsius.
  In the similar manner i would like to know about 1 H.P = 746.2 Watts
• 

  Viswanathan Chockalingam

  Hi Sachin,
  You want an apt answer?
  Actually 1 W= 1 J/s.So it means that energy transferred in one second.the energy may be in the form of Mechanical,Electrical,Thermal or Chemical or any other means.
  
  Now coming to HP, energy can be transferred at any rate. Higher transfer rate means higher ability to give more energy.The unit HP was introduced to compare the power of a machine to that of horse,that were used initially(As said in the reference).The motor power specifications will be in HP.It is also given in PS.(especially in car engines)
  
  finally 1 HP = Energy given by a horse in one second!
• 

  NAVATHE SACHIN

  So, one H.P is equal to energy given by a horse in one second. can you tell me how much a horse give energy in one second ?
• 

  Viswanathan Chockalingam

  That is 746
• 

  Viswanathan Chockalingam

  746 J
• 

  NAVATHE SACHIN

  Power = workdone/time (UNITS : J/S or watts) and 1 joule = 1 newton-meter.So, 1 H.P =746.2 watts or 746.2 n-m/s.This value indicates you require 746.2 newtons of force to the lift weight by one meter in one second.
• 

  Viswanathan Chockalingam

  Exactly
• 

  GAUTAM KUMAR MISHRA

  I think first pic speaks all things. It is not the matter that how can i say that how much work will be done by a horse in a second because we consider about the general case . It can vary according to the capacity of horse but we take general case and this (1 H.P.=746.2 watt ) is given by our former as other units.