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The diameter of the sun is `1.4 x 10^9m` and its distance from the earth is `1.5 x 10^11 m`. Find the radius of the image of the sun formed by a lens of focal length 20 cm. |
Answer» Correct Answer - C Here `u=-150x10^1cm` f=20cm Using lens formula `1/v-1/u=1/f` `rarr 1/v=1/20-1/(150x10^11)` `=(750x10^9-1)/(150xx10^11)` `=~=(750xx10^9)/(150x10^11)` `rarr v=(150xx10^11)/(750xx10^9)` `We know magnification `(m)=v/u=h_2/h_1` `rarr h_2-=v/uxxh_1` `=(150xx10^110/(750xx10^9xx150xx10^11)xx0.7xx10^11mm` `=0.93mm` |
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