In YDSE, how many maximas can be obtained on a screen including central maxima in both sides of the central fringe if

λ = 3000 Å, d = 5000 Å

Concept:

In Young's Double Slit Experiment (YDSE), the positions of bright fringes (maximas) are given by the formula:

y = nλD/d, where n is the order of the maxima (n = 0, ±1, ±2, ...), λ is the wavelength, D is the distance between the slits and the screen, and d is the distance between the slits.

For maximum number of maximas, we need to find the maximum value of n such that the path difference (nλ) does not exceed the slit separation (d).

Formula Used:

nλ ≤ d

Calculation:

⇒ nλ ≤ d

⇒ n ≤ d/λ

⇒ n ≤ 5000 Å / 3000 Å

⇒ n ≤ 5/3

⇒ n ≤ 1.67

Since n must be an integer, the maximum value of n is 1.

This means there are maximas at n = 0 (central maxima), n = ±1 on either side.

⇒ Total number of maximas including the central maxima = 3

∴ The correct answer is option 3.