level: Pressure in fluids
Questions and Answers List
level questions: Pressure in fluids
| Question | Answer |
|---|---|
| What's Upthrust? | Resultant force upwards (felt by objects submerged). If the upthrust is less than the weight of the object, it'll sink. If the upthrust is larger than the weight of the object, it'll float |
| What's the Relationship between Atmospheric pressure & height & How is it caused? | Atmospheric pressure decreases as altitude incereases. Because as the altitude increases: - the number of air molecules decreases - the weight of the air decreases - there is less air above a surface |
| What is the Atmospheric pressure at sea level & at the Cruising altitude of a passenger plane (why must aircrafts be pressurised?) | at sea level: 101,000 Pa (101 kPa) Cruising altitude of a passenger plane: 27,000 Pa (27 kPa) ∴ air crafts must be pressurised as humans cannot take in oxygen quickly enough to meet their bodies’ needs |