Recent content by John100

Why does water have a maximum density at +4 deg C ? Is water unique in having this peak in density not at an extremity of the temperature range of a single (i.e. liquid in the case of water) state? Is this property of water the single most important reason for life to have evolved on this planet?

Guys, thank you all for so much input and erudition. Frankly, I thought there would be a simple and straight forward answer. It's good to know that scientific debate is alive and well. I find it interesting that things, including air, are all trying to get to the centre of the Earth, but when...

Yes, it is really about the air pressure at the centre. Does it go to zero along with the net gravitational force?

If one could drill a hole to the centre of the earth, presumably the gravitational force on the body would decrease as one passed down this theoretical hole until one could float freely right at the centre where the gravitational force is equal and opposite in all directions with a net effect of...