sunlight/regular home light rays?

Question

do sunlight or like a regular home light say, in your kitchen have stronger uv ray?


this is for my science fair.

Answer 1

If it's for your science fair, you should do some experiments with sunlight, sunlight through a glass window, an incandescent lamp, and various kinds of fluorescent lamp.

Answer 2

Incandescent bulbs have filaments that are so cold, that UV radiation isn't a significant fraction of their emission spectrum. Incandescent bulbs mostly emit IR radiation, and the visible light is only the upper tail-end of their spectrum. This is why they glow yellow-ish in color, compared to the sun. Because their spectrum is dominated by low frequencies. Fluorescent lamps, be they the long tubes or the compact CFL spirals, internally generate UV as the original wave. That is what the mercury vapor emits by default. The bulb/tube contains an inner coating that we call phosphors (not necessarily anything to do with phosphorous), that will STEP DOWN the frequency of the UV into visible light. The phosphors will absorb the UV, and emit it in multiple stages, each of less energy per photon than the UV, hence a visible light is emitted. Tanning beds use fluorescent tubes, WITHOUT the phosphor inner coating of the tube. The tubes of tanning bed lamps, have bare glass. And a bare glass that is of a special type that is transparent to UV rays. Most glass types are opaque to UV rays, primarily. It is more difficult to find a UV-transparent glass type, than it is to find a UV-opaque glass type. So as long as your bulb has a glass container, and is not manufactured specifically to enable UV rays, you should have nothing to worry about.

Answer 3

I think most people would ask the question but not mention that this is for a science fair. But now that you mention it, I feel it's not fair for others to do your science fair.

If you can find the answers on Wikipedia, does it count as having done your work? I imagine you need to measure these lights.

If you are young, maybe you can get your parents to buy some solar beads / uv sensitive beads / energy beads. Then you can visually see where there is more uv light. You can even make necklaces with a few beads each, to give to your classmates.

If you are older, you can buy these yourself. I'll also give you some things to think of / search / discover online...


Normal ("incandescent") light bulbs convert 5% of energy to visible light and 95% to heat and _________ light (a type of non-visible light that is related to heat).

How are ultraviolet, infrared, and visible light (most importantly, blue and red light) related to each other?

Fluorescent lights have mercury inside, which would normally emit light at certain frequencies (called "mercury spikes" in "spectral power distribution").

Fluorescent lights also have a coating inside that converts most of this mercury light to visible light at a wide variety of frequencies (colors, combined to look white). The coating converts most light, but the spike frequencies and closer frequencies will still have more light. Are these spikes closer to blue or red in frequency?

"Black lights" are used in some clubs. It's easy to make them as fluorescent lights. What frequency of light do they produce?

Amount of total light: The unit of amount of light is lux. How bright is a sunny day? How bright is a brightly lit office? How bright is a full-moon night?

We can adjust to these light levels because our eyes are very flexible. Your kitchen may have less light than an office.