The heart of a man pumps 5 L of blood through  the arteries per minute at a pressure of 150 mm of mercury . If the density of mercury be 13.6 x 103 kg/ m3 and g = 10 m/s2, then the power of heart in watt is   from Physics Work, Energy and Power Class 11 Manipur Board
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The heart of a man pumps 5 L of blood through  the arteries per minute at a pressure of 150 mm of mercury . If the density of mercury be 13.6 x 103 kg/ m3 and g = 10 m/s2, then the power of heart in watt is  

  • 1.70

  • 2.35

  • 3.0

  • 1.50


A.

1.70

 Given, pressure = 150 mm of Hg
Pumping rate of heart of a man

 = fraction numerator d straight V over denominator d straight t end fraction space equals space fraction numerator 5 space straight x space 10 to the power of negative 3 end exponent over denominator 60 end fraction space straight m cubed divided by straight s

Power space of space heart space equals space straight P space. dV over dt space equals space ρgh space. space dV over dt space left square bracket space straight p equals space ρgh right square bracket

rightwards double arrow space fraction numerator left parenthesis 13.6 space straight x space 10 cubed space kg divided by straight m cubed right parenthesis left parenthesis 10 right parenthesis space straight x 0.15 space straight x space 5 space straight x space 10 to the power of negative 3 end exponent space over denominator 60 end fraction space equals space 1.70 space straight W

 Given, pressure = 150 mm of Hg
Pumping rate of heart of a man

 = fraction numerator d straight V over denominator d straight t end fraction space equals space fraction numerator 5 space straight x space 10 to the power of negative 3 end exponent over denominator 60 end fraction space straight m cubed divided by straight s

Power space of space heart space equals space straight P space. dV over dt space equals space ρgh space. space dV over dt space left square bracket space straight p equals space ρgh right square bracket

rightwards double arrow space fraction numerator left parenthesis 13.6 space straight x space 10 cubed space kg divided by straight m cubed right parenthesis left parenthesis 10 right parenthesis space straight x 0.15 space straight x space 5 space straight x space 10 to the power of negative 3 end exponent space over denominator 60 end fraction space equals space 1.70 space straight W

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