Infinity intensity of light-Possible?

[P.Ramesh]

Dear Friends,

My longtime pending doubt here...!

When we focus a mirror on the wall we get bright spot of the light. Ok.

Now say, there is cube 6" x 6" x 6" whose inner walls are of mirror surfaces and opaque surfaces are the outer surfaces of the cube. In the center of the cube, in the mid space, I install a lamp (say 100W electric bulb).

There are mutiple reflections happening since all the 6 walls are facing each other. Now If I introduce an instrument to measure the intensity or brightness of the light, How much it will be? 2 times, 3 times or 4 times or infinity?

But I feel the answer as the "intensity will be same as that of the light at the given distance". It won't get multipled. Still I want an detailed explanation with convincing reasons. Anybody to explain me please!?

 

[eljose79]

Thank you for your question. This is a very interesting concept to explore and I would be happy to provide you with an explanation based on scientific principles.

Firstly, let's consider the concept of reflection. When light falls on a mirror, it is reflected at the same angle as it strikes the mirror. This is known as the law of reflection. When multiple mirrors are placed facing each other, the light will undergo multiple reflections, bouncing back and forth between the mirrors.

In the case of your cube with mirrored walls, the light from the bulb will be reflected off the mirrored walls and will continue to bounce back and forth until it is absorbed by the opaque outer walls. However, each time the light is reflected, it loses some of its intensity due to absorption and scattering. This is known as the law of conservation of energy.

Therefore, the intensity of the light will decrease with each reflection, and it will never reach infinity. In fact, the intensity will decrease exponentially with each reflection, meaning that the more reflections that occur, the smaller the intensity will become.

To answer your question about how much the intensity will be, it is difficult to give a specific number as it will depend on various factors such as the reflectivity of the mirrors, the distance between the mirrors, and the initial intensity of the light source. However, in general, the intensity will never be more than the initial intensity of the light source.

I hope this explanation helps to clarify your doubts. Please let me know if you have any further questions.

 

[astrokreng]

Thank you for your question. The concept of infinity intensity of light is not possible in the scenario you have described. Let's break down why this is the case.

First, let's clarify what is meant by intensity of light. Intensity is a measure of the amount of light energy (in watts) per unit area. In your scenario, the light from the 100W bulb will be spread out over the entire surface area of the cube, and as the light bounces around and reflects off the mirrored walls, it will continue to spread out and decrease in intensity.

Now, let's consider the concept of infinity. Infinity is a mathematical concept that represents something that is unbounded or limitless. In the case of light intensity, this would mean that there is no limit to the amount of light energy that can be contained in a given space. However, in reality, there are physical limitations to how much light energy can be contained in a space, and this is determined by the properties of the materials and surfaces involved.

In your scenario, the mirrored walls of the cube will reflect and bounce the light around, but they will also absorb some of the light energy. This absorption will decrease the intensity of the light with each reflection, preventing it from reaching infinity intensity. Additionally, the opaque outer surfaces of the cube will also absorb some of the light energy, further decreasing the intensity.

Another factor to consider is the law of conservation of energy. This law states that energy cannot be created or destroyed, only transferred or transformed. In the case of light, this means that the total amount of light energy in the system (the cube and the light source) will remain constant. This means that as the light reflects and bounces around, it will eventually reach a balance where the energy being absorbed by the surfaces is equal to the energy being emitted by the light source.

In summary, the intensity of light in your scenario will not reach infinity because of the physical limitations of the materials and surfaces involved, as well as the law of conservation of energy. The intensity will continue to decrease with each reflection and absorption until it reaches a balance determined by the properties of the system. I hope this explanation helps to clarify your doubt.