If tube length of astronomical telescope is 105 cm and magnifying powe – McqOptions

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1.	If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objective [AFMC 1994]
A.	100 cm
B.	10 cm
C.	20 cm
D.	25 cm
Answer» B. 10 cm

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