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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:
0.50 m
Solution
u =-0.50 m = -50 cm
f = 0.20 m = 20 cm
Lens formula:
`1/f=1/v-1/u`
⇒`1/20=1/v-1/-50`
⇒`1/v=1/20-1/50`
⇒`1/v=(5-2)/100`
⇒`1/v=3/100`
⇒`v=100/3` cm
The image will be at a distance of 33.3 cm on the right side of the mirror
magnification `m=v/u`
`m=33.3/-50`
`m=-0.66`
magnification is negative therefore image will be real and inverted.
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