In the double-slit experiment of the figure, the viewing screen is at distance D
ID: 1791759 • Letter: I
Question
In the double-slit experiment of the figure, the viewing screen is at distance D = 4.68 m, point P lies at distance y = 21.3 cm from the center of the pattern, the slit separation d is 5.29 m, and the wavelength is 665 nm. What is the ratio of the intensity IP at point P to the intensity Icen at the center of the pattern?
the tolerance is +/-2%
In the double-slit experiment of the figure, the viewing screen is at distance D = 4.68 m, point P lies at distance y = 21.3 cm from the center of the pattern, the slit separation d is 5.29 m, and the wavelength is 665 nm. What is the ratio of the intensity IP at point P to the intensity Icen at the center of the pattern?
the tolerance is +/-2%
In the double-slit experiment of the figure, the viewing screen is at distance D = 4.68 m, point P lies at distance y = 21.3 cm from the center of the pattern, the slit separation d is 5.29 m, and the wavelength is 665 nm. What is the ratio of the intensity IP at point P to the intensity Icen at the center of the pattern?
the tolerance is +/-2%
Explanation / Answer
lambda = 665 nm, d = 5.29 mum
D = 4.68 m, y = 21.3 cm
position of p = 2 pi / lambda * d sin theta
= 2 pi / (665 * 10-9) * [5.29 * 10-6 (y/D)]
= 2 pi / (665 * 10-9) * [5.29 * 10-6 (21.3 * 10-2/4.68)]
= 2.27 rad
ratio of intensity I/I0 = 4 cos2 (2.27 / 2) = 4 cos2 (650)
= 0.714