Back to RAY OPTICS
JEE PHYSICS MCQ: RAY OPTICS
1
Medium
1 of 1
Application
+4 | -1
Magnifying power of an astronomical telescope in near point adjustment is of its magnifying power in normal adjustment. Then find the focal length of objective when the length of the telescope in normal adjustment is . (Take least distance of clear vision )
View answer and explanation
Correct option: C
Option C (7.5 cm) is correct because it is derived from the given magnifying power ratio and the length of the telescope in normal adjustment.
More Questions from RAY OPTICS
Practice All Chapter MCQs →
In refraction, light waves are bent on passing from one medium to the second medium, because, in the second medium
A double convex lens is made of glass which has its refractive index 1,45 for violet rays and 1.50 for red rays. If the focal length for violet ray is , the focal length for red ray will be
Which light rays undergoes two internal reflection inside a raindrop, which of the rainbow is formed?
A piece of plane glass is placed on a word with letters of different colours. The letters which appear minimum raised are
A dentist has a small mirror of focal length . He views the cavity in the tooth of a patient by holding the mirror at a distance of from the cavity. The magnification is
All of the following statements are correct except