Question

Two sources of light 0.5 mm apart are placed at a distance of 2.4 m and wavelength of light is 5000 Å. The phase difference between the two light waves interfering on the screen at a point at a distance 3 mm from central bright band is ____________.

पर्याय

• `6  pi  "radian"`

• `3.2  pi  "radian"`

• `2.5  pi  "radian"`

• `4  pi  "radian"`

Answer 1

Two sources of light 0.5 mm apart are placed at a distance of 2.4 m and wavelength of light is 5000 Å. The phase difference between the two light waves interfering on the screen at a point at a distance 3 mm from central bright band is `2.5  pi  "radian"`.

Explanation:

Using,

`"W" = lamda"D"/"d"`

` = (5000 xx 10^-10 xx 2.4)/(0.5 xx 10^-3)`

`= 2.4 xx 10^-3  "m"`

`= 2.4  "mm"`

`therefore "Number of fringes" = 3/2.4 = 1.25`

`therefore "Phase difference,"`

`Delta phi = 2"n"pi`

`= 2 xx 1.25  pi`

` = 2.5 pi  "radian"`