Question

The focal lengths of the objective and the eyepiece of the telescope are 225 cm and 5 cm respectively. The magnifying power of the telescope will be

• A. 49
• B. 54
• C. 35
• D. 60
• E. 65

Answer 1

Answer: (B)

54

Magnifying power of the telescope$=-\frac{f_o}{f_e}\times (1+\frac{f_e}{D})$ $=-\frac{225}{5}\times (1+\frac{5}{25})$ $=54$