A astronomical telescope has objective and eyepiece of focal lengths 40 cm and 4 cm respectively To view an object 200 cm away from the objective, the lenses must be separated by a distance

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Accepted Answer

Correct answer: B. (b) : Here f_0=4 0 cm, f_e=4 cm Tube length (^l)^= Distance between lenses =v_o+f_e For objective lens, u_o=−2 0 0 cm, ν_o=?. 1v_0− 1u_0= 1f_0or 1v_0− 1−2 0 0= 14 0 or 1v_o= 14 0− 12 0 0= 42 0 0∴v_0=5 0 cm ∴l=5 0+4=5 4 c m

$A astronomical telescope has objective and eyepiece of focal lengths 40 cm and 4 cm respectively To view an object 200 cm away from the objective, the lenses must be separated by a distance$

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