How to solve for angle of reflection in respect to floor?

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    Angle Reflection
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Homework Help Overview

The problem involves calculating the angle of reflection of light from a floor-to-ceiling mirror, given the positions of a student and a flashlight. The student is positioned at a specific distance from the mirror, and the heights of her eyes and the flashlight are provided.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to use inverse tangent to find the angle but expresses confusion about the setup and which triangles to consider. Participants suggest drawing diagrams to clarify the situation and question the accuracy of the original poster's drawing.

Discussion Status

Participants are actively engaging with the original poster's attempts, providing feedback on the drawing and suggesting that it should conform to the problem statement. There is a focus on ensuring the geometry accurately represents the scenario described.

Contextual Notes

There are uncertainties regarding the positioning of the flashlight relative to the student, with some participants suggesting assumptions about its placement. The original poster's understanding of the problem setup is still developing.

AngelLegs
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Homework Statement


A student stands 2.7 m in front of a floor-to-ceiling mirror. Her eyes are 1.64 m above the floor and she holds a flashlight at a distance 0.85 m above he floor.
Calculate the angle θ, in degrees, that the flashlight makes with respect to the floor if the light is reflected into her eyes.

Homework Equations


tangent
sine

The Attempt at a Solution


I'll use inverse tangent (1.64m/2.7m) to find the angle, but I'm not sure how to set it up. I'm confused about which angle I'm finding when I use that, and which "triangle" I'm supposed to be solving for, because the light ray makes a triangle when it reflects off the mirror, and the light makes another when it reflects into the students eyes. But I'm having huge complications with figuring which ones to apply to the problem solving process.
 
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Draw a diagram. Also, please don't use HUGE bold print. It's unnecessary and some of us view it as obnoxious, like screaming your question.
 
phinds said:
Draw a diagram. Also, please don't use HUGE bold print. It's unnecessary and some of us view it as obnoxious, like screaming your question.
I'm sorry, I'm new
I don't quite know how to use this website yet
Can you see the photo I posted?
 

Attachments

  • diagram.png
    diagram.png
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Yes. I think you have errors in your drawing in that not everything conforms to your problem statement. Another issue is that you don't know the distance of the light from the torso, so you must assume it to be zero (light is being held by side, not out front).

Get the drawing to exactly conform to the problem statement and you then have everything needed to solve this trivial problem.
 
phinds said:
Yes. I think you have errors in your drawing in that not everything conforms to your problem statement. Another issue is that you don't know the distance of the light from the torso, so you must assume it to be zero (light is being held by side, not out front).

Get the drawing to exactly conform to the problem statement and you then have everything needed to solve this trivial problem.
I'm afraid I'm not understanding what you mean.
Is it like this?
 

Attachments

  • diagram.png
    diagram.png
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You're getting the idea. I know you have the right idea but do you really think this is an accurate model of the problem? Why does the light not line up with the stated distance. Stop drawing a stick figure and just draw the geometry.
 

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