Problem 53PE

(a) A 75.0-kg man floats in freshwater with 3.00% of his volume above water when his lungs are empty, and 5.00% of his volume above water when his lungs are full. Calculate the volume of air he inhales—called his lung capacity—in liters. (b) Does this lung volume seem reasonable?

Solution

Step 1

A man is floating in freshwater. We have to find the volume of air that he inhales. Given the mass of man is 75.0kg

A)

By ignoring the weight of inheld we get where V is the volume of a man when the lung is full V’ is the volume when the lung is empty.

or

B)

The volume of deep breath is 2.00L, so the calculated volume 1.63L is good