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The normal lens on a 35-mm camera has a focal length of 50.0 mm . Its aperture diameter varies from a maximum of 25 mm (f/2) to a minimum of 3.1 mm (f/16)

Determine the resolution limit set by diffraction for f/2. Specify as the number of lines per millimeter resolved on the film. Take λ = 560 nm. (lines/mm)

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Final answer:

The resolution limit set by diffraction for an f/2 aperture on a 35-mm camera lens with a focal length of 50.0 mm, using a wavelength of 560 nm, is approximately 146 lines per millimeter.

Step-by-step explanation:

The question involves calculating the resolution limit set by diffraction for a 35-mm camera lens that has a focal length of 50.0 mm and an aperture diameter at its maximum of 25 mm (f/2).

Using the given wavelength of λ = 560 nm, the resolution limit can be found using the formula for the diffraction limit of a circular aperture, which is θ = 1.22λ/D, where D is the diameter of the aperture.

The limit of resolution R, in lines per millimeter, is then given by R = 1/(2θf), where f is the focal length of the lens

. For f/2, D = 25 mm and f = 50.0 mm, so:

Resolution limit calculation for f/2:
θ = 1.22 × 560 × 10-9 m / 25 × 10-3 m
θ = 2.73 × 10-5 radians
R = 1/(2 × 2.73 × 10-5 × 50 × 10-3)
R ≈ 146 lines/mm

Note: The actual calculation might differ slightly due to rounding.

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