The heart of a man pumps 5 litres of blood through the arteries per minute at

⇦

⇨

The heart of a man pumps 5 litres of blood through the arteries per minute at a pressure of 150mm of mercury. If the intensity of mercury be 13.6 x 10³ kg/m³ and g=10 m/s² then the power of heart in watt is

Options

(a) 3
(b) 1.5
(c) 1.7
(d) 2.35

Correct Answer:

1.7

Explanation:

WORK DONE W = F X D
F = PA (PRESSURE X AREA)
OR W = P A.D = P (AD) = P V
OR WORK DONE = PRESSURE X VOLUME
Given  P = 150mm OF Hg = 10⁵ * 150/760
= 15 x 10⁵ / 76 Pa
Volume, V = 5L = 5000 cm³ = 5×10^-3 m³
So, W = PV = (15 x 10⁵ / 76 ) x 5×10^-3
Work Done  = 98.68 Joules

Now pumping of 5L of blood is done in 1 min = 60 seconds
So, Power = Work done / time
OR POWER = 98.68 /60 = 1.64 watts

Related Questions:

1. A lead bullet of 10 gm travelling at 300 m/s strikes against a block
2. 540 g of ice at 0° C is mixed with 540 g of water at 80° C. The final temperature
3. Which one of the following bonds produces a solid that reflects light in the visible region
4. At a given temperature the root mean square velocities of oxygen and hydrogen
5. A solid which is transparent to visible light and whose conductivity increases

Topics: Work Energy and Power (94)
Subject: Physics (2479)

---

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

---

Share this page with your friends