-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 El 2017-11-21 a las 22:12 -0000, Wol's lists escribió:
On 21/11/17 21:46, Lew Wolfgang wrote:
On 11/21/2017 01:16 PM, Carlos E. R. wrote:
...
Note that (and yes this does sound weird) Helium is actually a metal.
You can get iron as a gas, too :-)
And it has all these weird properties that makes it useful for things like this. As mentioned, all gases have the same number of molecules per volume at any given temperature, so replacing Nitrogen (atomic weight 28 per molecule) with Helium (atomic weight 4) abrades less energy off the platter (lower friction :-) and the draught can't disturb the heads so much.
They do need some drought, to fly. With no friction (vacuum) the heads would crash.
The implication is the hydrogen (weight 2) would be even better, but I suspect the fact that helium is a noble gas has something to do with it.
It burns. It burns very well, even explode in the right mixture. I know that from personal experience :-) And it is more difficult to contain for 5 years.
As I said, Helium is a metal which is probably why, what heat is generated, helium conducts it away much better.
Maybe. I know nothing about why different gases may conduct heat differently, even if they do. - -- Cheers Carlos E. R. (from openSUSE 42.2 x86_64 "Malachite" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iF4EAREIAAYFAloUrJwACgkQja8UbcUWM1wYGgD/RlK1oIjq/6PoRNe7Vd0LG+5g djuzAjfqiTGUOBP1wsQA/0XDx4CA7Q+rhaYcIX1DVaiwvDC9X7XzpQVlsa0U9oK6 =dcS1 -----END PGP SIGNATURE-----