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The length of a telescope, for which it is known that it has an objective lens of focal length 144 c m and an eye piece of focal length 6 cm , is

Options

A1.5   m
B1.44   m
C1.38   m
D1.56   m

Correct answer

A. 1.5   m

Step-by-step solution

The length of a telescope is l = f 0 + f e Given, f 0 = 144   c m = 1.44   m ,   f e = 6.0   c m = 0.06   m l = 1.44 + 0.06 = 1.5   m

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