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Title: GR8677.100
Post by: conantee on January 08, 2010, 02:19:30 AM
100. The screen of the pinhole camera is at a distance D from the pinhole, which has a diameter d. The light has an effective wavelength \lambda. (\lambda <<D) For which of the following values of d will the image be sharpest?
(A) \sqrt{\lambda D
(B) \lambda
(C) \frac{\lambda}{10}
(D) \frac{\lambda ^2}{D}
(E) \frac{D^2}{\lambda}