Why doesn't the sky crush us all?

  • Context: High School 
  • Thread starter Thread starter doubleB
  • Start date Start date
  • Tags Tags
    Sky
Click For Summary

Discussion Overview

The discussion revolves around the question of why the atmospheric pressure does not crush humans despite the vast weight of air above us. Participants explore concepts related to fluid pressure, the nature of air, and the physiological responses of the human body to atmospheric conditions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that the pressure of fluids inside the body matches atmospheric pressure, preventing crushing.
  • Others argue that the weight of air is not as significant as it seems, with a square inch of air weighing approximately 14 pounds, and pressure decreasing with altitude.
  • A participant expresses confusion about the nature of air pressure, questioning if it acts like a weight and whether parts of the body would compress under such pressure.
  • Another participant explains that air pressure is exerted equally in all directions, leading to a net force of zero on the body.
  • Some participants discuss the effects of rapid altitude changes on pressure perception, such as ear popping during flights.
  • One participant mentions that while air pressure is significant, it is not comparable to the crushing force of a heavy object like a million-ton weight, which would create unequal forces.
  • Another participant illustrates the concept of air resistance using a demonstration involving a yardstick and newspaper.
  • A participant reflects on the adaptability of life to its environment, suggesting that if atmospheric pressure were harmful, humans would not exist to question it.
  • There are discussions about the effects of sudden exposure to a vacuum, including asphyxiation and other physiological responses.

Areas of Agreement / Disagreement

Participants express a range of views on the nature of air pressure and its effects on the human body, with no clear consensus reached. Some points are clarified, but confusion remains about specific aspects of pressure and its implications.

Contextual Notes

Participants acknowledge various assumptions about pressure, the nature of air, and the physiological responses of the body, but these assumptions are not fully resolved within the discussion.

  • #31
I guess I ought to start a new thread to ask my question.

It's a little off the Why Doesn't The Sky Crush Us All topic.
 
Physics news on Phys.org
  • #32
Just because there are "tons" of matter somewhere above you, doesn't mean it is exerting any force on you. Why does your roof not crush you? Because something is holding it up. The reason air doesn't crush you is because more air is holding the higher air up.

EDIT: Oh no, I thought you were asking it again, but its different.
 
Last edited:

Similar threads

  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 53 ·
2
Replies
53
Views
8K
  • · Replies 4 ·
Replies
4
Views
12K
  • · Replies 10 ·
Replies
10
Views
8K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
23
Views
8K
  • · Replies 5 ·
Replies
5
Views
5K
  • · Replies 25 ·
Replies
25
Views
5K