Three lenses having power $2, 2.5$ and $1.7 D$ are kept touching in a row. What is the total power of the lens combination ?

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Solution

Given:
$P_{1} = 2 D, P_{2} = 2.5 D, P_{3} = 1.7 D$
Let the total power of the lens combination be $P$ . Thus,
$P = P_{1} + P_{2} + P_{3} = 2 + 2.5 + 1.7 = 6.2 D$

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Three lenses having power 2,2.5 and 1.7D are kept touching in a row. What is the total power of the lens combination ?

Given:P1=2D,P2=2.5 D,P3=1.7 DLet the total power of the lens combination be P. Thus,P=P1+P2+P3=2+2.5+1.7=6.2 D

Three lenses having power $2, 2.5$ and $1.7 D$ are kept touching in a row. What is the total power of the lens combination ?

Given:
$P_{1} = 2 D, P_{2} = 2.5 D, P_{3} = 1.7 D$
Let the total power of the lens combination be $P$ . Thus,
$P = P_{1} + P_{2} + P_{3} = 2 + 2.5 + 1.7 = 6.2 D$