Question

Estimate the pressure ?heart (in pascals) generated by the left ventricle of a human heart during contraction.

Pheart= __________________Pa

Im not sure how to get this one started. I also looked at the book College physics 2nd edition by Freedman, and theres no info about it.

Here is the hint:

Model a human as a column of fluid under the influence of gravity.

In order to circulate blood throughout the body, the left ventricle must generate enough pressure to overcome gravity's effect on the blood from the head to the feet.

Use the fact that blood consists mostly of water.

Estimate the pressure Pheart (in pascals) generated by the left ventricle of a human heart during contraction Pa Pheart

Answer 1

Solution:

Density of blood = water density = 1000 kg/m^3

Gravity = 9.8 m/s/s

Assuming the height of a person to be 6ft =1.6 m,

Pressure in the left ventricle = P = density x gravity x height = (1000)(9.8)(1.5)

= 14,700 Pa

133.3 Pa = 1mmHg

=> 14700 Pa = 14700/133.3 mmHg  

=> Pressure = P = 110 mmHg in the left ventricle