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Author Topic: The Reflective Properties Of A Magnifying Mirror  (Read 3753 times)

Offline neilep

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The Reflective Properties Of A Magnifying Mirror
« on: 08/01/2008 21:18:44 »
Dear Sirs et Madams,

See this mirror:



It's a two sided magnifying mirror.

Wifey has one !...and it's still intact !

Why does the side that magnifies my face the biggest reflect the light of a bulb on the ceiling as a smaller area than the side that magnifies the less ?...do you understand what I mean ?..ie: The side that is no magnification , projects a larger blob of light than the other side which does magnify.


Thanks

Neil




 

Offline Soul Surfer

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The Reflective Properties Of A Magnifying Mirror
« Reply #1 on: 09/01/2008 00:28:25 »
Because a magnifying mirror is one that brings the light to a focus when you reflect light from a flat mirror the reflected image of alight is (when its square on) the same size as the mirror.  the magnifying mirror bends the light towards a focus bit to get a prope magnifies image you must be inside the focus and so produces a smalle reflection if you get the diatance just right you can project an image of the light bulb.
 

Offline turnipsock

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The Reflective Properties Of A Magnifying Mirror
« Reply #2 on: 09/01/2008 02:45:01 »
What is the focal length of the mirror?
 

Offline neilep

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The Reflective Properties Of A Magnifying Mirror
« Reply #3 on: 09/01/2008 03:43:46 »
THANK YOU IAN..I believe I understand !

See peeps....even my questions get answered !!

TURNIPSOCK......I'll try and obtain the focal length on the morrow...May I ask why ?

...I could do it now but it'll mean tip toeing and fiddling in the dark and that'll wake wifey !...I suppose I'll need a tape measure eh ?
 

lyner

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The Reflective Properties Of A Magnifying Mirror
« Reply #4 on: 10/01/2008 14:59:46 »
http://www.glenbrook.k12.il.us/GBSSCI/PHYS/Class/refln/u13l3d.html
Have a look at this. Ray tracing is a good way of predicting how mirrors and lenses will affect light.
With a concave lens, the rays from an object are converged when reflected. You can get a 'real' image, through which light rays actually pass (are focused in front) or a 'virtual' image, from which they appear to come; the virtual image appears to be behind the mirror and further away and bigger. It depends on how far away the object is.
If you look at yourself with the mirror at different distances, you can get both conditions and the image 'explodes' at the distance where the rays are parallel.
A plane (flat) mirror produces just 'virtual' images - what you see is not really behind the mirror, of course.
A convex mirror diverges the rays so the image is always virtual and behind the mirror.
 

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The Reflective Properties Of A Magnifying Mirror
« Reply #4 on: 10/01/2008 14:59:46 »

 

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