Two point sources S 1 and S 2 separated by a distance 10   μ m emit light waves of wavelength 4…

Two point sources S1 and S2 separated by a distance 10 μm emit light waves of wavelength 4 μm in phase. A circular wire of radius 40 μm is placed around the sources as shown in figure, then (O is the centre of the circle and OS1=OS2)

  1. Points A and B are dark and points C and D are bright
  2. Points A and B are bright and point C and D are dark
  3. Points A and C are dark and points Band D are bright
  4. Points A and C are bright and points B and D are dark

Solution

In cases of B & D the path, the difference is zero so phase difference is also zero gives bright image while in case of A & C path difference is, 10 μm

⇒∆p=10 μm

and we can calculate there are 104λ=52λ, which gives dark fringe.

Asked in: AP EAMCET 2018 (25 Apr Shift 1)

Practice more Wave Optics questions on Aicharya