Difference between convex lens formula and convex mirror formula

AI Thread Summary
The discussion clarifies the differences between the formulas for convex lenses and convex mirrors. For convex mirrors, the focal length is considered negative, while for convex lenses, it remains positive. The formula used for both is 1/f = 1/do + 1/di, but the sign conventions differ based on the type of optical device. Specifically, concave mirrors and convex lenses have positive focal lengths, whereas convex mirrors and concave lenses have negative focal lengths. Understanding these conventions is crucial for correctly applying the formulas in optics.
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Homework Statement



difference between convex lens formula and convex mirror formula




The Attempt at a Solution



for convex mirror you make focal point negative and use the 1/f = 1/do + 1/di

but for convex lens do you do the same?

you don't make the f negative i think am i right?

thank you
 
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Correct. So for the record, the sign convention for f is:
Positive: Concave mirror, convex lens
Negative: Convex mirror, concave lens
 
thank you
 
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