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प्रश्न
The erect image formed by a concave mirror is of size double the size of object. How are u and v related?
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उत्तर
Magnification is
m = `"I"/"O" = 20/"O" = 2`
∵ m = `-"v"/"u"`
∴ `-"v"/"u"` = 2
∴ v = -2u
But , u is always negative
∴ v = 2u
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