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Can light amount be double with mirror? Education 

Can light amount be double with mirror?

When this question come to mind, with it a lot of answers start circulating as well in our mind. First one if it so then why we are wasting lot of energy in lightning the bulbs why not just light one bulb and double triple its light with the help of mirror. The whole city street will be lighted with a few bulb or some mirror which mean a lot of energy saving. Even our home can as whole lighted with one bulb light isn’t that amazing.


Well the answer is like a puzzle solver to many of us. and it take a little time to understand. The use of mirror has been used for centuries, if some one ask me to give some example; i definitely give the example of lighthouse on shore of sea. That has been used to mark dangerous coastal areas for ships in past. The working of lighthouse is some like this a mirror is place behind the burning fuel to redirect it light to different places. But the question remain the same is it doubling the amount of light? Well the answer is no. it is just reflecting the light without increasing the amount of light.


As many of us don’t even knows Reflection and Refraction but here some answer from across the world what they have to say about this.

If you shine a light into a mirror, does the fact that the light is reflected back mean that you are effectively doubling the amount of light in the room? If so, couldn’t the energy problem be at least partially solved by filling rooms with mirrors? If not, why not?

Mark Lloyd, Bath UK
  • A room lined with mirrors would be more brightly lit than one lined with the usual mixture of wallpaper, wood, windows, etc. The mirrors would reflect most of the light falling on to them back into the room, whereas wallpaper absorbs most of the light reaching it. This would mean that someone reading the Guardian in a mirrored room with a 60 watt bulb would see the page as more brightly lit than in a normal room with the same bulb. However, the difference would be slight if the room was normally furnished as usual with chairs, carpets, cats, etc. It would have even less effect on the energy crisis as a lot of energy is used for things like cooking, cleaning, computers, etc. and not just for lighting.
    Robin Wilson,
  • Yes and no. Mirrors can’t create light, only reflect it. Normally, much of the light from an electric light is absorbed by the walls of a room (and a lot is also reflected which is why you can see!). Mirrors are much more reflective and will bounce the light back so of course they can be used to increase the general brightness in a room. However, the light will not bounce around indefinitely; even mirrors absorb some of the light that hits them and eventually the reflected light would dim to the point that it made no difference. If this were not true, the entire world could be lit with one bulb and a very large number of strategically positioned mirrors!
    Max Wurr, Stanmore United Kingdom
  • No, you would not increase the amount of light in the room. The light waves are merely being reflected off of the mirror. To add more light to the room, you would have to increase the amount of light waves being emitted. The reflection only changes the path of the waves, not the amount or intensity of the light.
    Kayla Iacovino, Tempe United States
  • Yes. “Daylighting” is the science/technology behind avoiding waste of light when it is absorbed in walls and other surfaces. On the simplest level you paint walls light colours to reflect light and brighten a room (unlike a teenager who finds it hard to read in her dark painted cavern despite lightbulbs and daylight)
    Craig Napier, Eagle Heights Australia
  • Firstly, a light source only emits a certain amount of energy, so we can dispense with the idea of solving the world’s energy problems with mirrors. If you shine a light into a mirror, you simply divert the energy in another direction. If the questioner is talking about placing a mirror behind a light source such as a table lamp or candle, the mirror only reflects the light which would otherwise have been absorbed by the wall. There is more light in the room, to be sure – but only because you’re wasting less of it.


To find out more you can view detailed answer on  Link1 and Link2