In a telescope the object glass of focal length 14 cm, is located at 20 cm from the diaphragm. The focussing lens is midway between them when a staff 16.50 m away is focussed. The focal length of the focussing lens, is (A) 5.24 cm (B) 6.24 cm (C) 7.24 cm (D) 8.24 cm

In a telescope the object glass of focal length 14 cm, is located at 20 cm from the diaphragm. The
focussing lens is midway between them when a staff 16.50 m away is focussed. The focal length of
the focussing lens, is
(A) 5.24 cm
(B) 6.24 cm
(C) 7.24 cm
(D) 8.24 cm
by

1 Answer

Answer :

(C) 7.24 cm
by

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