Women and overweight people often experience backpain. Let us explore the reason for this. Assume
the women has a weight of 60.0 daN before pregnancy. Suppose she gains 10.0 daN during pregnancy,
due to weight of the fetus, placenta, amniotic fluid, etc. To make the calculation easy, but still realistic,
we shall model the unpregnant women as a uniform cylinder of diameter 0.30 m. We can model the
added weight due to the fetus as a 10.0 daN sphere with a 25.0 cm diameter and centered about 5.00
cm outside the woman’s original front surface.
(a) By how much does her pregnancy change the horizontal location of the woman’s center of gravity?
Kinda depends on where you decide to place the prenatal sphere...and the original height of the she-cylinder.
To determine how the woman's pregnancy changes the horizontal location of her center of gravity, we need to calculate the moment of each component of her weight distribution.
1. Calculate the moment of the abdomen:
The abdomen can be modeled as a uniform cylinder of diameter 0.30 m. The center of gravity of a uniform cylinder is at its center. Therefore, the horizontal location of the abdomen's center of gravity remains unchanged.
2. Calculate the moment of the added weight due to the fetus:
The added weight due to the fetus is modeled as a 10.0 daN sphere with a 25.0 cm diameter. The center of gravity of a sphere is at its center. Since the sphere is centered about 5.00 cm outside the woman's original front surface, the horizontal location of the fetus's center of gravity is 5.00 cm.
3. Calculate the total moment:
To calculate the total moment, we need to sum up the moments of each component. Since the abdomen's center of gravity remains unchanged, we can ignore it and only consider the moment due to the added weight of the fetus.
Moment = Weight x Distance
Moment = 10.0 daN x 5.00 cm
Moment = 50.0 daNm
Thus, the pregnancy changes the horizontal location of the woman's center of gravity by 5.00 cm.