In short, a compression wave, which carries information about the disappearance of the upward force, has to travel down the Slinky to the bottom end before that end "knows" that the Slinky has been dropped, and that it should fall. And it takes time for that information to propagate down through the Slinky." "No motion at the bottom end, until the bottom end gets the information that the tension has changed. "The simplest explanation is that the bottom end is sitting there minding its own business, with gravity pulling it down, and tension pulling it up equal and opposite forces," Cross said. It seems to hover in the air, defying the laws of physics, before finally falling to the ground with the rest of the coil but in fact this behavior makes perfect physical sense. When you hold up a Slinky, then let go, the bottom remains stationery until the rest of the coil has collapsed down on top of it. (Image credit: VeeX (opens in new tab) | Shutterstock (opens in new tab))Īs demonstrated by University of Sydney physics professor Rod Cross in the above video, a classic Slinky toy exhibits some truly startling physics. Fortunately, commercial plasma lamps are low-power enough that it doesn't hurt when the electric current passes along the filament, through the glass and into your hand. This is why a plasma filament will seem to be attracted to your hand when you touch the ball. Placing your hand near the glass alters the electric field that exists between the central electrode and glass orb, effectively strengthens the force that draws electrons outward. Their escape routes are the plasma filaments visible in the lamps. An ionized gas is called a plasma.īecause electrons try to flow as far from one another as possible (repelled by each other's negative charges), they shoot outward from the central electrode in every direction toward the outer glass orb. The current ionizes the atoms, giving them an electric charge and simultaneously causing them to emit flashes of light.
When the lamp is plugged in, a high-frequency electric current flows into the electrode, and from there, passes to the gaseous atoms surrounding it. The smaller sphere at the lamp's center is an electrode an electrical conductor that is used to transfer electricity from a circuit to a surrounding vacuum. These clear glass orbs are filled with a mixture of non-reactive gases such as helium, neon and krypton kept at less than one-hundredth the pressure of the outside air. Plasma lamps (or globes) are beautiful visual displays of a very strange variety of matter. (Image credit: Creative Commons | Diliff)
0 kommentar(er)
