
Instrument that is used for seeing the moon, stars and planets.

Important Questions on Wave Optics






Given below are two statements : one is labeled as Assertion and the other is labeled as Reason .
Assertion : For a simple microscope, the angular size of the object equals the angular size of the image.
Reason : Magnification is achieved as the small object can be kept much closer to the eye than and hence it subtends a large angle. In the light of the above statements, choose the most appropriate answer from the options given below:

An astronomical telescope has an objective lens of focal length and an eyepiece of focal length . Find the angular magnification of the telescope.




The focal lengths of objective lens and eye lens of a Galilean Telescope are respectively 30 cm and 3.0 cm. Telescope produces virtual, erect image of an object situated far away from it at least distance of distinct vision from the eye lens. In this condition the Magnifying Power of the Galilean Telescope should be :





Draw the ray diagram of an astronomical telescope when the final image is formed at infinity. Write the expression for the resolving power of the telescope.




