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Light Radiation Q

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Yes, it is. Simply because the closer you get to the sun (as it is the source of all of our light) the more powerful it gets. Although there is no air in space for heat, so most of it is radiant energy (light shining on something and giving it heat).

 

Kind of like staring into a spotlight from two feet away, compared to a mile away.

 

edit: Although this does sound suspiciously like your homework.

  • Author

Yes, you only told me an observation, but why does this happen....?

as you get closer to the sun the intensity of the light increases.

 

a m^2 on earth will get hit by a certain number of photons every second, as you get closer this will increase resulting in a larger heating effect.

Imagine building a huge spherical solar panel around the sun. It will have a surface area of [math]4 \pi R^2[/math] where [math]R[/math] is its radius. Every photon coming out of the sun will hit the solar panel so all of the Sun's energy will be caught. Let's call that energy [math]E[/math].

 

So we have spread the energy [math]E[/math] over an area [math]4 \pi R^2[/math], so there will be [math]\frac{E}{4 \pi R^2}[/math] of energy for every unit area on the panel.

 

Now, if we half the radius, bringing the sphere closer to the sun, the E remains the same (since we haven't changed the sun!), but we need to take our formula and replace [math]R \rightarrow R/2[/math]. This gives

 

[math] \frac{4E}{4 \pi R^2}[/math]

 

so the energy per unit area has increased by a factor of 4!

 

This is why the sun appears hotter as you get closer.

  • Author

Awesome!.... Then i found out how to develope an equation for this question. It's a function energy at distances from a source. I was thinking of this question and i got the same equation for light radiation.....What scientist developed this answer

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