MCQ
The resolving power of a telescope can be increased by increasing:
- AWavelength of light.
- BDiameter of objective.
- CLength of the tube.
- DFocal length of eyepiece.
✓
Answer
- Diameter of objective.
Explanation:
The resolving power of a telescope can be given as:
Resolving power $=\frac{1}{\text{d}(\theta)}=\frac{1}{1.22\lambda/ \text{D}}=\frac{\text{D}}{1.22}$ (wavelength)
So, resolving power can be increased by decreasing the wavelength and increasing the diameter of objective.
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