It's a radiant barrier to reflect heat. Light bulbs are heaters, particularly incandescent and halogen bulbs. Fiberglass+foil is a better insulator than either alone.
The foil backing is attached to a thin layer of insulation. The combination of the foil and the insulation deflects the heat from the light bulbs away from the ceiling where the electrical wires are located. Removing the foil insulation may cause the fixture to operate in an unsafe manner.
The purpose of the foil faced insulation is to provide a thermal break between the potentially Very Hot incandescent bulbs and the ceiling/electrical connections. The equivalent brightness LED bulbs generate a fraction of the heat and don't require the thermal barrier.
Yes, foil reflects light because it has a metallic light interaction. Is placing aluminum on your light dangerous (it's too bright)? Well, you get reflector / spot light bulbs which have a silvered coating over part of them, so you're probably OK if you don't cover it completely.
Additionally, if the aluminum is not securely attached to the light source, it can pose a risk of electrical shock or burn if it comes into contact with the hot bulb.
Aluminum is such a good conductor of electricity that even aluminum foil can be used as a conductor. Foil tends to be too delicate for most industrial applications, but it just goes to show the advantages of this material.
So the very reflective color of the white paper was more reflective than glass# sheen and transparency. This data suggests that mirrors reflect more light energy than many common substances. Aluminum foil reflects more light energy, however, if clouds block direct sunlight.
The shiny side of aluminum foil reflects more light than the dull side. This is because the shiny side is a smoother surface than the dull side,...
Aluminum (Al) is an only material having a high reflectance to the ultraviolet light in a wavelength range of 250 nm to 400 nm. A lightweight aluminum foil having high workability is suitable for the ultraviolet light reflecting material.
Some scientific studies have shown that the aluminum present in common kitchen items like cooking utensils, containers and foil can potentially leach the metal into your food. The key is understanding how much – or, really, how little – aluminum you're getting when you use foil.
If you do cook spicy or acidic foods in foil, you may notice a white substance that wasn't there before you heated it; that's aluminum salt. It's created when the heated aluminum reacts with the acid in the food.
When aluminum is rubbed against the rust, the aluminum loses electrons, while the iron oxide (the rust) gains electrons, turning back into metal. The aluminum acts as a reactive surface that removes the rust, while also creating a layer of oxide that prevents the metal from rusting further,' she explains.
Protection Against Intruders
The aluminum foil will make it harder for them to grip the doorknob, and it will also create a loud noise if they try to turn it. This noise can alert you to their presence and give you time to call for help or defend yourself.
Windows magnify heat, so by using foil you're reflecting the sun off the window, sending it away from your home. 'Blocking your windows with tin foil will help to keep your rooms cooler in the heat as it reflects the heat back outside,' explains Adam Pawson, Head of Digital, Safestyle.
Emergency management agencies specifically recommend using aluminum foil-covered cardboard that goes between windows and drapes.
So, now that you know the reason behind the different appearance of the two sides, you're probably wondering if you should use aluminum foil with the shiny side up or down. Quite simply, it doesn't matter. Since both sides are made of the exact same material, they will perform exactly the same way.
Q: Why does foil darken or discolor sometimes during baking? A: That discoloration is aluminum oxide, a harmless substance that is naturally present on the surface of the foil. When the foil comes in contact with moisture, it can accelerate the buildup of aluminum oxide.
Material makeup: Tin foil was made with thin leaf tin and sometimes combined with lead. Aluminum foil is made from an alloy that is between 92 and 99 percent aluminum. Cost: Aluminum foil is significantly cheaper to make than tin foil. As an added bonus, it's also more efficient and effective.
The best surfaces for reflecting light are very smooth, such as a glass mirror or polished metal, although almost all surfaces will reflect light to some degree. Reflection of Light When light waves are incident on a smooth, flat surface, they reflect away from the surface at the same angle as they arrive.
While steel is a common choice, other metals, such as brass, copper and aluminum can also be used to block or shield against magnetic fields, but they are not as effective as iron or steel.
Use aluminium foil to create a reflector
Your router can be boosted by reflecting the signal outwards. To do a makeshift reflector, use aluminium foil (good ol' tin foil). Cut about 30cm of foil and try to get it a curved shape.
Does the shiny side reflect more heat while the dull side is a better conductor? The answer is no, as both sides serve the same purpose, and there is no one 'better' side. The reason why aluminium foil has two different sides is because of a manufacturing process called milling.