Calculating a Mirror's Reflection
Date: 08/08/99 at 18:30:58 From: Brandon Subject: Optics: find angle and point P If you shine a light on a mirror to illuminate an object (<1 = <2), show how to find point P. object . | \ | \ <1 | \ | \|P /| / | / <2| light / | mirror
Date: 08/09/99 at 03:43:21 From: Doctor Floor Subject: Re: Optics: find angle and point P Hi, Brandon, Thanks for your question. Let's suppose that you are given the position of the light, the object, and the mirror. Bring the object over to the position of its reflection in the mirror: drop the perpendicular altitude from the object to the mirror, and then make the altitude segment twice as long. Then draw a segment from the reflection of the object to the light. Of course the light should be shining straight to the reflection of the object. The segment meets the mirror at the point P you are looking for. object . | . reflection of object \ | / \ | / \ | / \|/ /|P / | / | light / | mirror If you need more help, just write us back. Best regards, - Doctor Floor, The Math Forum http://mathforum.org/dr.math/
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