MCQ
A reflecting telescope has a large mirror as its objective with radius of curvature equal to $80\,cm$. The magnifying power of this telescope if eye piece used has a focal length of $1.6\, cm$ is
- A$100$
- B$50$
- ✓$25$
- D$5$
✓
Answer
Correct option: C.
$25$
c
$\mathrm{f}_{0}=\frac{\mathrm{R}}{2}=\frac{80}{2}=40 \mathrm{\,f}_{\mathrm{e}}=1.6$
$\mathrm{f}_{0}=\frac{\mathrm{R}}{2}=\frac{80}{2}=40 \mathrm{\,f}_{\mathrm{e}}=1.6$
$\mathrm{m}=\frac{\mathrm{f}_{0}}{\mathrm{f}_{\mathrm{e}}}=\frac{40}{1.6}=25$
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