Q.
In a single slit diffraction experiment, the width of the slit is made double its original width. Then the central maximum on the diffraction pattern will become
The angular width of the central maximum is given by:
2Dλ/a where a is the width of the slit.
If the value of a is doubled, the angular width of the central maximum decreases to half its earlier value. Due to this, the intensity of the central maximum will be increased to four times.
This implies that the central maximum becomes much sharper. Thus the central maximum becomes much narrower and brighter.