The SYSTOLIC pressure in a major artery is measured at 115 mmHg. What is the net force on a 1 cm2 section of the artery wall if the absolute pressure in the tissue outside the arterial wall is 108.6 kPa?
a mmHg equals 133.3 Pa (google conversion)
find the pressure difference (in kPa)
a Pascal is a Newton per m^2 ... 10^4 cm^2
To determine the net force on a section of the artery wall, we need to consider the pressure difference across the wall. The formula to calculate the net force is:
Net Force = Pressure Difference × Area
First, we need to convert the units so that they are consistent. Let's convert the systolic pressure from mmHg to kPa.
1 mmHg is approximately equal to 0.1333 kPa.
115 mmHg × 0.1333 kPa/mmHg = 15.3295 kPa
Now we can calculate the pressure difference:
Pressure Difference = Absolute Pressure - Systolic Pressure
Pressure Difference = 108.6 kPa - 15.3295 kPa
Pressure Difference = 93.27 kPa
Next, we need to convert the area from square centimeters to square meters, as pressure is usually measured in pascals (Pa), which is equivalent to N/m^2.
1 cm^2 is equal to 0.0001 m^2.
Now we can calculate the net force:
Net Force = Pressure Difference × Area
Net Force = 93.27 kPa × 0.0001 m^2
Net Force = 9.327 N
Therefore, the net force on a 1 cm^2 section of the artery wall is 9.327 N.