Ray diagrams for mirror ray tracing

AI Thread Summary
There is confusion regarding the sign convention for object distance (o) in ray diagrams for concave mirrors. Hyperphysics states that o is usually negative, while Hecht suggests it should be positive for real objects located to the left of the mirror. This discrepancy leads to different results when applying the mirror equation. The consensus among participants is that Hyperphysics is incorrect in this context. Clarifying the sign convention is essential for accurate ray tracing and understanding optics.
RickyWong
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Just a check here...

I'm doing some ray diagram practice for optics and I've hit a road block. Hyperphysics is stating that for a concave mirror o is usually negative due to it measured against the direction of light propagation when applied to the mirror equation (below).

\frac{1}{o}+\frac{1}{i}=\frac{1}{f}

But Hecht, says that if it is a real object to the left of the mirror, it should be positive (which incidentally gives me the correct answer to a question I'm attempting)

Is Hyperphysics wrong? or have I misinterpreted it?

here's the link:
http://hyperphysics.phy-astr.gsu.edu/hbase/geoopt/mirray.html#c4
 
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I agree with you: Hyperphysics is wrong.
 
vela said:
I agree with you: Hyperphysics is wrong.

Thank you.
 
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