Explanation

In Young's double slit experiment, angular fringe separation is given by

\[ \theta = \frac{\lambda}{d} \]

where \( \lambda \) is wavelength and \( d \) is slit separation.

Angular separation depends only on wavelength and slit separation. It does not depend on the distance of screen from the slits.

Hence, moving the screen away does not change angular separation. Therefore, Statement I is false.

If wavelength increases, then

\[ \theta \propto \lambda \]

So angular separation increases. Therefore, Statement II is true.

Hence the correct option is Statement I is false but Statement II is true.

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