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# Physics/optics

Question
sir i want to ask which is the correct formula for finding the number of images formed between two plane mirrors?
n = 360/x - 1 , where x is the angle between the two mirrors
or 360/x and if this value comes even subtract one and if odd keep the value as it is.
is it necessary that the number of images formed in two mirrors is always odd?
if the angle between the two mirrors is 120
is the number of image 2 by the first formula or 3 by the second formula.
totally confused..
thanks
john

Really you'll need to draw me a picture or be more specific.  Are they attached at the edge?  Where is the object?  I think I'm more confused by the way you asked this question than you are.  Follow up if you can add some details or upload a drawing, preferably the drawing, and I'll give it my best shot.

Physics

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#### Dr. Stephen O. Nelson

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I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.

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