A combination of two thin lenses in contact have power +10D. The power reduces to +6D when the lenses are 0.25 m apart. The power of individual lens is

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Accepted Answer

Correct answer: D. (d) :P_1+P_2=10D (i) P_1+P_2-dP_1P_2=6D (ii) 10-0.25P_1P_2=6 (iii) Using equation (ii), we have ∴ 10-60.25=P_1P_2 ;P_1P_2=16 P_1-P_2= (P_1+P_2)^2-4P_1P_2= 10^2-4 16 P_1-P_2=6 Using equation (i) and (iii), P_1=8D ,P_2=2D

$A combination of two thin lenses in contact have power + 10 D . The power reduces to + 6 D when the lenses are 0.25 m apart. The power of individual lens is$

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