May 19, 2015 · Humphrey Davy invented the safety lamp in 1815 to prevent naked flame igniting the so-called fire-damp gas in mines. I believe that basically a gauze shield surrounded the flame.

May 28, 2010 · Sir Humphrey Davy managed to solve this problem by enclosing an oil lamp with a metal gauze, so even if the atmosphere inside the gauze became explosive the flames couldn't move through the gauze making the lamp safe to use.

Aug 14, 2015 · Kat - And finally, here's our Gene of the Month, and this time it's Lava lamp. Named after the popular and somewhat hypnotic 1960s decorative lighting fixture, Lava lamp was first identified in fruit flies in the year 2000 when researchers were looking for genes involved in helping cells to split in two as they divide in the early embryo. Like the coloured bubbles in the

Sep 3, 2006 · A real lava lamp works on the same principle of changing the density of something so it will float and then not. It consists of two immiscible waxes, one slightly denser than the other. The denser one is heated up by the lamp at the bottom, which makes it expand slightly, become less dense so that it will float in the other one.

Feb 26, 2015 · The DC current, moving through a static magnetic field will produce a force on the light globe which lasts for a few seconds, and in a consistent direction. This may be enough to stress & break the lamp filament (but I don't know enough about the tensile strength of sintered tungsten above 1000C to comment).

Feb 11, 2011 · The (quartz) lamp is subject to stress from the heat of the light bulb: different parts are at widely different temperatures. Mechanical stressing a piezoelectric material causes it to become electrically charged.

Sep 26, 2007 · I thought the formulae provided made that clear, but to reiterate. If the current is held constant an increase in Resistance will lead to an increase in power dissipated hence an increase in brightness. This is not what happens when the lamp is supplied with a constant voltage as is the normal case in a domestic installation, in this case an increase in Resistance results in a decrease in ...

Feb 28, 2015 · I have noticed in winter when the limbs are bare there is an optical illusion that occurs when one places a tree between oneself and a street lamp. Whenever a bare tree is backlit the limbs seem to be growing in concentric circles around the light. A bare tree at night With the light behind the tree.

May 3, 2010 · The fact Hg boils before it mixes with the other molten metal depends on the temperature so you don't need to try melting Hg with Cu because Cu melts at 1089°C at certainly at that temperature Hg boils off immediately. You can nontheless make an amalgam with Cu at lower temperatures. If you want to melt the other metal you have to use lower m.p. metals, for example tin, and a big, closed ...

Maybe it can also depend on the fact that the organic film on the glass surface absorbs light more than glass, increasing the glass temperature and so reducing its life. Another consequence should be the fact shorter wavelenghts are absorbed from the film, reducing the whiteness of the light emitted from the lamp.