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 13.6 103 kg/m3 and g = 10 m/s2 then the power (in watt) is
- 3.0
- 1.50
- 1.70
- 2.35
Answer
(3) 1.70
Solution
Pressure: P = h g = 0.150 13.6 103 10 = 2.04 104 Pa
Volume pumped per second: Vt = 5 10-360 m3 s-1
Power = P Vt
= 2.04 104 5 10-360
= 1.70 W
Answer: (3)