# Tag Info

### Why the pressure of atmosphere doesn't crush you when you e.g. walk outside?

Pressure acts in all directions. it does not care about direction. pressure is a property of the fluid itself. but the way you CALCULATE it is to find the 'weight of the air above'. this does not mean ...

### If you decreased the mass of a planet, but kept the mass of the atmosphere the same, would the air density decrease?

In an isothermal atmosphere, the density is given approximately by $$\rho = \rho_0\exp(-\mu gh/k_BT)\ ,$$ where $\mu$ is the mean mass of a particle, $h$ is the height above ground level and $g$ is ...
1 vote

### If you decreased the mass of a planet, but kept the mass of the atmosphere the same, would the air density decrease?

Yes the air density would decrease. The density is proportinal to $e^{-g*h/T}$ where g is the local force of gravity h is the height and T is the tenperature. Lower gravity gives lower pressure and ...
Accepted

### Would a straw work in a completely sealed container?

No. If the air can't get in the container in any way other than the straw than you won't get any water. A tiny amount of water may go up the straw a bit but it wouldn't be a reasonable amount to drink....

### Does dusk really remain for a shorter period of time at the equator?

I get the sense that the OP might have been wondering about what seems like a riddle: if people near the equator are moving faster (due to the earth's rotational speed), shouldn't they "go ...
In the range of pressures we have in the troposphere the gas law holds perfectly, but we have to interprete it in a proper way. Lest's solve for P the equation of the gas law: $$P=\frac{n} {V}RT$$ ...