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प्रश्न
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:
0.15 m
उत्तर
u = -15 cm
f = 20
Substituting these values in the lens formula, we get:
`1/f=1/v-1/u`
`1/20=1/v-1/-15`
`1/20=1/v+1/15`
`1/20-1/15=1/v`
`1/v=(3-4)/60`
`1/v=-1/60`
v=-60 cm
The image will be formed at a distance of 60 cm in front of the mirror.
`m=v/u`
⇒`m=(- 60)/-15`
⇒m=4
Magnification is positive; therefore, the image is virtual and
erect.
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संबंधित प्रश्न
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