Question

When the distance of separation between the slit and screen is doubled, the angular separation between fringes in single slit diffraction pattern experiment

• A. increases
• B. decreases
• C. remains same
• D. first increases and then decreases

Hint:

The fringe angle is lambda over a, with no D.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
In a single slit diffraction pattern, the angular position of the first minimum is given by \(a\sin\theta=\lambda\). The angular separation between fringes depends on \(\lambda\) and slit width \(a\) only.

Step 2: Apply:
\[ \theta\approx\frac\lambda a \]
There is no screen distance \(D\) in this expression.

Step 3: Effect of doubling D:
The linear fringe width \(\beta=\dfrac{\lambda D}{a}\) doubles, but the angle subtended at the slit stays the same.

Step 4: Choose:
Option (C), remains same.

Final Answer:
Angular separation does not depend on the screen distance. \[ \boxed{C:\ \text{remains same}} \]