If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectiveA. 100 cmB. 10 cmC. 20 cmD. 25 cm

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

1.	If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectiveA. 100 cmB. 10 cmC. 20 cmD. 25 cm
Answer» Correct Answer - C (c ) Given, `f_(o)+f_(e)`=105 `f_(o)+f_(e)/20 = 105` `f_(o)=100 cm` `f_(o)+f_(e)=105 cmand f_(o/(f_(e))=20 cm`

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If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting, calculate the focal length of objectiveA. 100 cmB. 10 cmC. 20 cmD. 25 cm

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