What is the power of the combination of a con | vedclass

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(A) The power of a lens is given by the formula $P = \frac{1}{f(m)}$, where $f$ is the focal length in meters.For a convex lens, the focal length is p

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Zero

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(A) The power of a lens is given by the formula $P = \frac{1}{f(m)}$, where $f$ is the focal length in meters.For a convex lens, the focal length is positive, so $f_1 = +0.25 	ext{ m}$. Thus, $P_1 = \frac{1}{0.25} = +4 	ext{ D}$.For a concave lens, the focal length is negative, so $f_2 = -0.25 	ext{ m}$. Thus, $P_2 = \frac{1}{-0.25} = -4 	ext{ D}$.The power of the combination of lenses in contact is the algebraic sum of their individual powers: $P = P_1 + P_2$.Substituting the values, $P = 4 	ext{ D} + (-4 	ext{ D}) = 0 	ext{ D}$.

What is the power of the combination of a convex lens and a concave lens of equal focal length $25 \text{ cm}$?

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