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Question
Find the nature, position and magnification of the images formed by a convex lens of focal length 0.20 m if the object is placed at a distance of:
0.25 m
Solution
u = -25 cm
f = 20 cm
⇒`1/f=1/v-1/u`
⇒`1/20=1/v-1/-25`
⇒`1/v=1/200-1/25`
⇒`1/v=(5-4)/100`
⇒`1/v=1/100`
⇒`v=100` cm
The image will be formed at a distance of 100 cm behind the mirrror.Magnification,
⇒`m=v/u`
⇒`m=100/-25`
`m=-4`
Magnification is negative, which means the image is real and inverted.
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