MCQ
In a $YDSE$ apparatus, we use white light then :
- Athere will not be a completely dark fringe.
- Bthe central fringe will be white.
- Cthe fringe next to the central will be violet
- ✓All of the above
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.



a wire of length $4 \pi$ meter. If an electric current of $4 \pi \sqrt{3} \mathrm{~A}$ is flowing through the sides of the polygon, the magnetic field at the centre of the polygon would be $x \times 10^{7} \mathrm{~T}$. The value of $\mathrm{x}$ is______.