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Find the distance from the mirrors for 4 reflections

  • #1
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1

Homework Statement


Two plain mirrors are put parallelly and 20 cm from each other. A source of light is put between the mirrors, 5 cm away from one. Find the distance from the mirrors of 4 first reflections.

Homework Equations


a1=a2 The distance of the object from the mirror and the reflection from the mirror is equal.

The Attempt at a Solution


http://s32.postimg.org/507dau85h/image.png
is it right?
 

Answers and Replies

  • #2
CWatters
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I know what a "first reflection" is but I'm not sure how you can have four of them in this situation. I think two are first reflections and two are second reflections. Check the distance for the one I marked incorrect.

image.png
 
  • #3
56
1
I know what a "first reflection" is but I'm not sure how you can have four of them in this situation. I think two are first reflections and two are second reflections. Check the distance for the one I marked incorrect.

View attachment 100962
5 should be replaced with 10. Am I right?
 
  • #4
CWatters
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Yes.
 

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