A tree and a mirror on the ground

AI Thread Summary
A plane mirror on the ground allows a person to see the top of a tree using the principle of similar triangles. The person is 1.6 m tall and positioned 2.1 m from one end of the mirror, while the tree is 35 m from the other end. The correct relationship involves the heights and distances from the mirror, but the individual is struggling to apply the formula correctly. Clarification is needed on which edge of the mirror reflects the tree's top. Additional resources, including a figure and hints, are available to assist with the problem.
sklotz
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Homework Statement



A plane mirror made of a very thin piece of glass lies flat on the ground. As shown in the following figure, one end of the mirror is 2.1 m from you and the other end is 35 m from a nearby tree. You are 1.6 m tall, and the mirror has a length L. The mirror is arranged so that you can just see the image of the top of the tree at one edge of the mirror. how tall is the tree?

Homework Equations



I know you have to use the principle of similar triangles

The Attempt at a Solution



I tried using height of person/distance of person from mirror = height of tree/distance of tree from mirror . This is similar to a problem our TA did in class and I thought I was using the correct formula, however, I have been unable to get the correct answer and I don't understand what I am doing wrong and only have one attempt left for credit
 
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Any chance you could show the figure?

What edge does he see the top of the tree? the edge that is closer to the man, or the edge that is closer to the tree?

I believe you answer will be in terms of L. Unless L has a value?
 
A figure and some hints are given on the second page of this file:
http://web.ics.purdue.edu/~jensend/media/pdf/phys221/homework/hints10.pdf

But note the numbers in the problem are different.
 

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