An astronomical telescope has an eyepiece of focal length 5 cm. If the angular magnification in normal adjustment is 10, the distance between the objective and the eye piece is
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Question

An astronomical telescope has an eyepiece of focal length 5 cm. If the angular magnification in normal adjustment is 10, the distance between the objective and the eye piece is

G1 Physics · Accepted Answer

Derived solution: Step 1: For an astronomical telescope use angular magnification |M| = fₒ/fₑ and, in normal adjustment, tube length = fₒ + fₑ. Step 2: Substitute the values given in the question and apply the geometry/sign convention shown. Step 3: On simplification the result is 55 cm. Therefore the correct option is C.