Solving Plane Mirror Question: How Far is the Flagpole?

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To determine the distance from the flagpole, convert the flagpole's height of 8.5 m to centimeters, making it 850 cm. The area of the mirror is 900 cm squared, which can be used to find its dimensions. A sketch of the situation can help visualize the problem using similar triangles. Consistency in units is crucial, so it's recommended to use the metric system (mks). This approach will lead to the solution for how far the observer is from the flagpole.
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If you hold a 900cm squared plane mirror 45 cm from your eyes and can just see the full length of an 8.5 m flagpole behind you, how far are you from the pole.



I am doing mirror/lens questions and for some reason this one stumps me. I am assuming that the 8.5 m has to be changed to cm. However, i have been dealing with questions of radius of curvature and focal length and then this one seems really easy but it has stumped me? can anybody help please?
 
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dev-hud said:
If you hold a 900cm squared plane mirror 45 cm from your eyes and can just see the full length of an 8.5 m flagpole behind you, how far are you from the pole.



I am doing mirror/lens questions and for some reason this one stumps me. I am assuming that the 8.5 m has to be changed to cm. However, i have been dealing with questions of radius of curvature and focal length and then this one seems really easy but it has stumped me? can anybody help please?

Convert the area you are given for the mirror into its height. Then use a sketch to figure out the triangles to get to the answer. And yes, you need to be consistent with your units. I'd put everything in mks, myself.
 

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