I'll soon be seeing the famous formula [tex]PV=nRT[/tex] in my course although I already learned it years before when I was in high school. So don't be too hard on me for my question please. My question is : if there is some gas (krypton or any other gas) in light bulbs and that the tungsten in it is really hot (around 4000K if I remember well), why don't the bulb explode under the gas' pressure? I guess it's because the choice of the gas is such that the gas don't expand that much. But still, 4000K seems really hot to me. Or is it because the bulb is really tough? Or both? Thanks.