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: Relate angle and width:
$\theta=\dfrac{\text{linear width}}{D}$.

Step 2: Substitute:
$\theta=\dfrac{\lambda D/a}{D}=\dfrac\lambda a$.

Step 3: Result:
$D$ cancels, so the angular separation is unchanged. Option (C).

Final Answer:
Angle = linear width / D, and D cancels. \[ \boxed{C} \]