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Name:  Philip R.
Status: student
Age: 17
Location: N/A
Country: England
Date: 2000-2001

Dear scientist,

I am a student in England and need your help, I am currently running an investigation to see whether steel has comon reflective properties as a mirror has, I know that the Energy given out from a bulb is 1/r(squared) but i am not sure how to follow this equation when it is reflected off a mirror into a L.D.R. Please can you help me?


If the surface is flat and perfectly shiny, then 1/r^2 still applies, with r being the total distance traveled: distance to the mirror added to distance back from the mirror. If the surface is curved, thing are a bit more complicated. Use optics to locate where the image being seen in the mirror is located. For "r", use the distance from the final image to the location of the device measuring the intensity. If using lenses, you may have to allow for energy lost in the lens.

Dr. Ken Mellendorf
Illinois Central College

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