Question

in a young double slit experiment wave of wavelength lambda incident on the two slits in phase. they travel to a point on the screen to produce a second minimum of the interference pattern the difference in

Answer 1

λ = y • d / (m • L)

, Young devised and performed an experiment to measure the wavelength of light. As discussed in the previous part of this lesson, it was important that the two sources of light that form the pattern be coherent. The difficulty confronting Young was that the usual light sources of the day (candles, lanterns, etc.) could not serve as coherent light sources. Young's method involved using sunlight that entered the room through a pinhole in a window shutter. A mirror was used to direct the pinhole beam horizontally across the room. To obtain two sources of light, Young used a small paper card to break the single pinhole beam into two beams, with part of the beam passing by the left side of the card and part of the beam passing by the right side of the card. Since these two beams emerged from the same source - the sun - they could be considered coming from two coherent sources. Light waves from these two sources (the left side and the right side of the card) would interfere. The interference pattern was then projected onto a screen where measurements could be made to determine the wavelength of light.

Answer 2

Assertion: In Young's double slit experiment using white light, the central fringe is white, the violet coloured fringe will be seen nearest to the central fringe. Reason: Red coloured fringe will be seen near central fringe.