I have no idea where to start with this plane mirror question

AI Thread Summary
To solve the plane mirror question regarding the rear-view mirror dimensions, it's essential to visualize the setup by drawing light rays from the top and bottom of the rear window to the driver's eyes. The concept of similar triangles is crucial, as it helps determine the necessary dimensions of the mirror based on its distance from the driver's eyes. The minimum height of the rear-view mirror can be calculated using the proportions derived from these triangles. Similarly, the minimum width can be established by applying the same principles. Understanding these geometric relationships is key to finding the correct answers.
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Homework Statement



does anyone know how to do this plane mirror question?
The rear window in a car is approximately a rectangle, 1.29 m wide and 0.330 m high. The inside rear-view mirror is 0.480 m from the driver's eyes, and 1.27 m from the rear window. What is the minimum height of the rear-view mirror if the driver is to be able to see the entire height of the rear window in the mirror without moving her head?


Calculate the minimum width of the rear-view mirror if the driver is to be able to see the entire width of the rear window in the mirror without moving her head.



Homework Equations


i don't know of one

The Attempt at a Solution


i haven't been able to get the right answer no matter what i do
 
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You need to make a drawing.

If you draw the light rays, top and bottom of back window to the focus of the eye, they are straight lines, you should note that you have similar triangles and hence the distance of the mirror to the eye will determine how big the mirror must be to be able to have the whole window seen.
 
thnx
 
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