MCQ
Identify which of the following color light, when passed through a double-slit opening, will produce the widest central band of light on the screen?
- ✓Red
- BOrange
- CYellow
- DBlue
✓
Answer
Correct option: A.
Red
Fringe width $\beta= \frac{\lambda\text{D}}{\text{d}}$ where $\lambda $ is the wavelength of the light used
$\Rightarrow\beta\propto\lambda$
As wavelength of the red light is the largest among the visible light, thus fringe width is the greatest formed due to red light.
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