A telescope has an objective lens of focal length $120\,\text{cm}$ and an eyepiece of focal length $5\,\text{cm}$. Its magnifying power is
A12
B20
C24
D125
Answer & Solution
Correct answer: C. 24
For a telescope, $m=f_o/f_e$. Thus $m=120/5=24$. So the telescope produces an angular magnification of 24.
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