Hi everyone,

Try to figure out this question:

Breathing 100% oxygen at 40000 ft is equivalent to breathing ambient air at:

18 000 ft

8 000 ft

10 000 ft X

14 000 ft

However, if we do the calculation, breathing 100% O2 (unpressured) at 40000ft (=187hPa) is equivalent to 187hPa partial pressure of O2.

With 21% of O2 in ambient air and a simple calculation, we can determine that 187hPa partial O2 pressure is reached when the ambient pressure is (187/0,21)=890hPa (roughly 3700ft).

The answer is consistent with all the questions about that subject but I just don't understand why.

If anyone can help,

Thanks

Try to figure out this question:

Breathing 100% oxygen at 40000 ft is equivalent to breathing ambient air at:

18 000 ft

8 000 ft

10 000 ft X

14 000 ft

However, if we do the calculation, breathing 100% O2 (unpressured) at 40000ft (=187hPa) is equivalent to 187hPa partial pressure of O2.

With 21% of O2 in ambient air and a simple calculation, we can determine that 187hPa partial O2 pressure is reached when the ambient pressure is (187/0,21)=890hPa (roughly 3700ft).

The answer is consistent with all the questions about that subject but I just don't understand why.

If anyone can help,

Thanks

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