An image is magnified by 2.50, concave mirror confusion wee

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Homework Help Overview

The problem involves a concave mirror with a specified radius of curvature, where the image produced is magnified by a factor of 2.50. The original poster is trying to determine the distance from the mirror to the object (the man's face) based on this information.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to find the object distance without having the image distance, leading to confusion. Some participants suggest using simultaneous equations to relate the object distance and image distance, while others recommend finding a relationship between these distances before applying the lens equation.

Discussion Status

The discussion has progressed with participants providing guidance on using simultaneous equations and relationships between distances. The original poster reports a successful calculation of the object distance, indicating some productive direction in the discussion.

Contextual Notes

The original poster expresses confusion regarding the lack of an explicit image distance, which is a key component in solving the problem. There is an emphasis on using relationships derived from magnification and mirror equations.

mr_coffee
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Hello everyone< i think I'm on the right track but now I'm stuck.
Here is the problem:
A concave shaving mirror has a radius of curvature of 37.0 cm. It is positioned so that the (upright) image of a man's face is 2.50 times the size of the face. How far is the mirror from the face?

Here is my work and drawing:
http://suprfile.com/src/1/6mwvik/lastscan.jpg I'm conufsed on how I'm suppose to find the object distance if I'm not giving the image distance.
 
Last edited by a moderator:
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Simultaneous equations. You have both of them. Two unkowns, di and do.
 
Chi Meson said:
Simultaneous equations. You have both of them. Two unkowns, di and do.
like he said
instead of using the hi-ho (:smile:) relation find a relation between di and do.

sub into your lens equation and you're all set.
 
Awesome thanks a lot guys worked great!
11.1cm for object distance, o yes!
 

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