2015 AIPMT-II Mechanical Properties of FluidsPressure and power Easy Question 31 of 34 in Mechanical Properties of Fluids

The heart of a man pumps 5 litres of blood through the arteries per minute at a pressure of 150 mm of mercury. If the density of mercury be $13.6\times10^3$ kg/$m^3$ and g = 10 m/$s^2$ then the power of heart in watt is:

A 1.50
B 1.70
C 2.35
D 3.0

The answer is B.

Solution

Pressure: $P = \rho gh = 13.6\times10^3\times 10\times 0.15$ Pa
Pumping rate: $\frac{dV}{dt} = \frac{5\times10^{-3}}{60}$ $m^3$/s
Power $= P\frac{dV}{dt} = \frac{13.6\times 5\times 0.15}{6} = 1.70$ W

Concept Power = pressure × volume flow rate

Mechanical Properties of Fluids in past papers

34 questions from this chapter have appeared across 14 exam years.