Question

A human heart pump 50cc of blood per heart beat at a pressure of 1.5 m of water if heart are 75 per minute then average pumping power of heart is (g =10 $m{s}^{-2}$ )

Answer 1

Step 1: Given

Volume of blood pumped per beat = 50 cc

Pressure = 1.5 m of water

Numer of heart beats per minute = 75

$g=10m{s}^{-2}$

Step 2: Formula used and Calculation

Pressure of 1.5 m of water = hρg

=$1.5\times 10\times {10}^3=1.5\times {10}^{4}Pa$

Now. Number of heart beats = 75 per minute

Work done per beat = $1.5\times {10}^4\times 50\times {10}^{-6}=0.75J$

Work Done for 75 beats = $75\times 0.75J$

Average Pumping power

$=\frac{Totalworkdone}{time}$

$=\frac{75\times 0.75}{60}$

$=0.93watt$