Q. 375.0( 1 Vote )
The power of a converging lens is 4.5 D and that of a diverging lens is 3 D. The power of this combination of lenses placed close together is :
A. + 1.5 D
B. + 7.5 D
C. - 7.5 D
D. - 1.5 D
P = 1/f (m)
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