Question

1. over a 1.5 hour workout, a crossfit athlete was measured to exhale a total volume of 18420 L of air at a rate of 75 breaths per minute. Calculate the volume of each breath taken by this athelete?

a) 0.3664 L/breath

b)2.73 L/breath

c) 2072250 L/breath

d) 124335000 L/breath

2. Calculate the volume of air that an adult person breaths in a record breaking 2 hour marathon. Assume that each breath has a volume of 5.75 L and the person breathes 110 times a minute?

a)75900 L

b)1265 L

C)140.56 L

D)9.565 L

3. Patients with COPD should avoid short term exposure to air containing more than 200 ppb of ozone. Which statement is true?

a) 200 ppb is equal to 1 billion parts of ozone per 1 billion particles

b) 200 ppb is equal to 200 ozone molecules per 1 billion particles

c) 200 ppb is equal to 200 ozone molecules per 1 hundred particles

d) 200 ppb is equal to 200 ozone molecules per 1 million particles

Answer 1

Q1. 1.5 hour = 1.5 x 60 = 90 minutes

Total volume exhaled = 18420 L

Rate = 75 breaths per minute

In 1 minute athlete can take 75 breaths

In 90 minutes number of breaths = 90 x 75 = 6750 breaths

Volume exhale per breath = Total volume exhale/ number of breaths in 1.5 hour = 18420/6750 = 2.73 L/breath

Hence b option is correct

Q2. 2 hours = 2 x 60 = 120 minutes

In 1 minute person can take 110 breaths

In 120 minutes number of breaths = 120 x 110 = 13200 breaths

For 1 breath volume of air = 5.75 L

For 13200 breaths volume of air = 5.75 x 13200 = 75900 L

Hence a option is correct

Q3. 200 ppb means 200 parts per billion

Hence b) 200 ppb is equal to 200 ozone molecules per 1 billion particles is correct option