If the two slits of double slit experiment were moved symmetrically apart with small relative velocity v and the distance between screen and mid-point of slits is fixed and equal to D. Consider a point P on the screen at a distance x from central maxima then (xltltltD):

Options

A. Rate of change of number of fringes between central maxima and point P changes with respect to time is `(xv)/(lambdaD)`
B. number of fringes contained between central maxima and point P increases with time
C. fringe width decreases as time passes
D. fringe width increases as time passes

Explanation

To solve the problem, we need to analyze the situation in the double slit experiment where the slits are moving apart with a small relative velocity \( v \). The distance between the screen and the midpoint of the slits is fixed at \( D \), and we are considering a point \( P \) on the screen at a distance \( x \) from the central maxima.

### Step-by-Step Solution:

1. **Understand the Initial Setup:**
- The double slit experiment involves two slits separated by a distance \( d \).
- The distance from the slits to the screen is \( D \).
- The point \( P \) is at a distance \( x \) from the central maxima on the screen.
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