Optics mirrors problem with rearview of car

AI Thread Summary
The discussion revolves around determining if a driver can see the entire width of a car behind them using a rearview mirror. The driver is 40 cm from the mirror, which is 23 cm long, while the car behind is 2.5 m wide and 4 m away. Initial calculations suggest visibility, but there are concerns about the accuracy of the drawn diagram and the similarity of triangles used in the analysis. The key issue is the measurement reference point for the 4 meters, which needs clarification. Overall, the conclusion is that the current approach may not yield the correct answer due to inaccuracies in the diagram and calculations.
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Homework Statement


I'm riding my car. My eye is 40cm from the rearview mirror. I want to know if I can see the car behind me. The car behind me is 2.5m large. Can I entirely see the car behind me in his whole wideness? The mirror is 23 cm long. The car is 4 meters behind us.


Homework Equations


Reflection laws.
Similar triangles.


The Attempt at a Solution


So, I drew this triangle (look attachment). And found that the eye, from where he his, can see the whole car. But, the question is not too clear. Do you think my steps are good?
 

Attachments

  • Photo pour Yu2.jpg
    Photo pour Yu2.jpg
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Where is the 4 meters measured from, the eye or the 23 cm mirror ? I think you have the correct answer though, at least app[roximately.
 
Your diagram is confusing and not accurate. The triangles are not similar.
40/23 is not equal to 4/2.5
 

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