MCQ
A microscope is used with sodium light and its resolving power is not sufficiently large. Higher resolution will be obtained by using wavelength of:
- A20 micron
- B2 micron
- C1 micron
- D400$\mathring{\text{A}}$
✓
Answer
- 400$\mathring{\text{A}}$
Explanation:
Since power of resolution is more for violet than for red, we conclude that resolving power is greater for light with lower wavelengths.
Wavelength of sodium light is around 589nm.
Hence resolving power increases for light with lower wavelength.
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