an object of height 5 centimetres is kept at a distance of 20 cm from the optic centre of a convex lens of focal length 8 centimetre the height of the image is
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h=5cm
u=-20cm
f=8cm
h'=?
1/v-1/u=1/f
1/v-1/-20=1/8
1/v=1/8-1/20
1/v=5-2/40
1/v=3/40
v= 40/3cm
m=v/u
= 40/3/-20
= -2/3
m=h'/h
-2/3 =h'/5
-10/3=h'
-3.333cm =h'
Height of image is 3.333cm from the lens
u=-20cm
f=8cm
h'=?
1/v-1/u=1/f
1/v-1/-20=1/8
1/v=1/8-1/20
1/v=5-2/40
1/v=3/40
v= 40/3cm
m=v/u
= 40/3/-20
= -2/3
m=h'/h
-2/3 =h'/5
-10/3=h'
-3.333cm =h'
Height of image is 3.333cm from the lens
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