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Question
What is meant by magnification? Write its expression. What is its sign for the (a) real (b) virtual, image?
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Solution
Magnification is the ratio of the length of image to the length of the object.
m = `1/"O"`
It is also given as
m = `-"v"/"u"`
Where, u and v is the object and image distance, respectively.
Hence, we have
- For real image: u and v are negative. So, m is negative.
- For virtual image: u is negative and v is positive. So, m is positive.
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