Physicsmedium · Past Paper
What is the power of a combination of two lenses with powers +2D and -1D in contact?
A+3 D
B+1 D
C-3 D
D-1 D
✓ Correct Answer: B — +1 D
The total power is the algebraic sum: P = P1 + P2 = 2 + (-1) = +1 D.
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