Question

For explaining the pressure / stress phenomenon, analyze three cases given below: (also include a sketch showing the pressure / stress situation inside and outside the suit/vehicle)

1. An astronaut at moonwalk

2. A submarine at 200 m depth

3. An airplane at 35000 feet with an internal air pressure of 0.7 atm

Answer 1

solution: using guage pressure as reference pressure.

• case1-
• when we talk about the moon it's gravity is 6 times lesser than the earth. which means that pressure outside the suit will be six times lesser than the atmospheric pressure on earth. but the inside pressure is maintained around 20.7- 11.7 kpa pressure. so that temperature and oxygen solubilty will be maintained.

• case2-
• pressure at 200m depth is = Patm+1000*9.81*200=2063325Pa=2063.325kpa
• but pressure inside the submarine approximately about the atmospheric pressure.

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• case3:
• pressure at 35000ft=Patm-pressure at 35000ft=101.325-104653.08=-104551.755KPa this will be outside pressure.
• and inside pressure is 0.7atm.