The effect of flight maneuvers on the heart The amount of

QUESTION:

The effect of flight maneuvers on the heart The amount of work done by the heart’s main pumping chamber, the left ventricle, is given by the equation

                            \(W=P V+\frac{V \delta v^{2}}{2 g}\)

where\(W\) is the work per unit time, \(P\) is the average blood pressure, \(V\) is the volume of blood pumped out during the unit of time,  (“delta”) is the weight density of the blood, \(v\) is the average velocity of the exiting blood, and g is the acceleration of gravity.

When P, V,  and  remain constant, W becomes a function of g, and the equation takes the simplified form

        \(W=a+\frac{b}{g}\) (a, b, constant).

As a member of NASA’s medical team, you want to know how sensitive \(W\)W is to apparent changes in g caused by flight maneuvers, and this depends on the initial value of g. As part of your investigation, you decide to compare the effect on W of a given change dg on the moon, where \(\(g=5.2 \mathrm{ft} / \mathrm{sec}^{2}\)\) with the effect the same change dg would have on Earth, where \(\(g=32 \mathrm{ft} / \mathrm{sec}^{2}\)\). Use the simplified equation above to find the ratio of \(d W_{\text {moon }}\) to \(d W_{\text {Earth }}\).

Equation Transcription:

dWmoon

dWEarth

g = 5.2 ft/sec2

g = 32 ft/sec2

Text Transcription:

W=PV + V delta v^2/2g

P

W

V

W=a+b/g

dW_moon

dW_Earth

g = 5.2 ft/sec^2

g = 32 ft/sec^2