Question

Suppose you measure a standing person's blood pressure by placing the cuff on his leg 0.560 m below the heart. calculate the pressures you would observe (in units of mm hg) if the pressure at the heart were 119 over 80 mm hg. assume there is no loss of pressure due to resistance in the circulatory system (a reasonable assumption, since major arteries are large).

Answer 1

162.63 mm hg over 123.63 mm hg

Step-by-step explanation:

The total pressure is equivalent to the addition of the heart pressure and pressure due to blood flow (ρ*g*h). Mathematically, we have:

`P_(T) = P_(H) + P_(B)`

`P_(T)` is the total pressure,
`P_(H)` is the pressure at the heart, and
`P_(B)` is the pressure due to blood flow in his leg.

`P_(B)` = blood density*height*9.81

The density of human blood is approximately 1060 kg/m^3

`P_(B)` = 1060*0.56*9.8 = 5817.28 pascal

We need to convert pressure from pascal to mm hg by multiplying by 0.0075

5817.28 pascal = 43.63 mm hg

Thus, the total pressure will be:

(119+43.63) mm hg over (80+43.63) mm hg = 162.63 mm hg over 123.63 mm hg

Answer 2

The first pressure describes the illustration of the extreme output of the heart; the second is because of the elasticity of the arteries in maintaining the pressure between beats.

Solution:

760 mm HG is equivalent to 13.6*.760 m =10.34 m H2O
Then multiply: 560/10.34 * 760mmHg to each of the readings. The answer is about 41 mmHg add this to the current reading of 120/80
Therefore: ΔP = 41 mm Hg, Leg blood pressure is 160/121.