Angular Magnification and Magnifying Power of Optical Instruments

[@ericsuh620]

Yet another Indian comrade saving my day

[@rev_5728]

3 years later, the guy just saved another mans day

[@carlosmartinezcairo7711]

3 weeks later, the guy just saved another mans day

[@aSenseSeeker]

@@carlosmartinezcairo7711 6 days later and 6 days before a final exam I am saved also. But its different for me, I am already an Indian

[@vimalkrishna9561]

5 months later saved yet another mans day

[@The--V]

9 months later 6 days before exam this indian guy helped another indian guy!

[@shashikantlagwankar6756]

Dear Sir, you have explained magnification in very simple scientifica language! Great!

[@ratishkumar3514]

Very nice teacher

[@jetlyvory]

great video sir.. But I have a query... It is weird but .. in the telescope.. why do we define these angles only and the ratio of beta and alpha to be magnification... i know its obvious that i cannot have an angle alpha when the object is at ddv.. because placing it at ddv is not possible... i just want an explanation why do we choose these two angles only.. and not some other angle... ;[ also why can't we place the object in front of the lens and not at angle... may be its a manipulation to avoid a point image at infinity.... expecting a explanation... :) thanks for the upload

[@ticklinks3344]

In a telescope .. the light rays are coming from infinity and converge on focus. So how do we assess magnification in such a case? Notice the angle subtended by the Objective is case of Telescope is same as what the object subtends to the naked eye. So the Objective is not helping in magnification. It is just creating a real image to be now magnified by the eyepiece. For the eyepiece - the image formed by Objective can now be positioned at the focal length of the eyepiece (for relaxed vision) or between the eyepiece and the focal length of the eyepiece - to form image at DDV. So like in case if a simple magnifying glass - we use the Angle subtended by the "Final Image / Object on an unaided eye" as magnification.

[@vishichaurasiya4427]

I get my desired topic......

[@Hunar1997]

Thanks