a and b Q (a) If one of two identical slits producing interference in Young's experiment is covered with glass, - Physics - Wave Optics

Question

a and b
Q (a) If one of two identical slits producing interference in
Young's experiment is covered with glass, so that the light passing
through it is reduced to 50%, find the ratio of the maximum and
minimum intensity of the fringe in the interference pattern
Q (b) What kind of fringes do you expect to observe if white light
is used instead of monochromatic light ?

Aarushi Mishra · Accepted Answer

QaWe know that, for constrictuve interference resultant intensity, Imax=I1+I22Also, for destructive interference resultant intensity, Imin=I1-I22ImaxImin=I1+I22I1-I22Let I1=I then acording to question,  I2=50% of I=I2ImaxImin=I+I22I-I22ImaxImin=1+1221-122ImaxImin=2+122-12ImaxImin=2+1+222+1-22ImaxImin=3+223-22ImaxImin=3+223-22×3+223+22ImaxImin=3+22232-222=3+2229-8=3+222Qb, If we use white light then fringes of all seven colours will be obtained
 The position of fringes of a particular colour will be same to what one would have obtained by using monochromatic light of that colour