Numerical problems based on thin film of uniform thickness

[@JustGo0d]

Sir at 19:30 The in ques nothing is mentioned Whether its reflected or transmited how did u identify formula Also sir u wrote reflected system D.i. condition is minina but u wrote maxima formula

[@itsmytube2133]

Sir why we used the 2n-1 lambda/2 formula ,why not 2n+1lambda /2

[@EngineeringPhysicsbySanjiv]

You can use (2n+1)λ/2 also. But then n=0,1,2,3...

[@karanrajeshirke8767]

Sir in last Question it is mentioned Destructive how you use formuale of maxima then ..formuale should be of minima na?

[@EngineeringPhysicsbySanjiv]

because reflection t denser medium took place two times. So lambda/2 is added two times.

[@rahulmathur5443]

At 10:16 why are we taking n=1

[@EngineeringPhysicsbySanjiv]

For minimum thickness of the film

[@divyranjanroutray775]

In 2nd Q why you didn't convert the thickness of film from CM to Angstrom??

[@EngineeringPhysicsbySanjiv]

That can also be done.. I have written answer directly in Angstrom

[@gaurideshmane8766]

Sir what if range of wavelength is not given in question? How to get the answer

[@Lolu-z6z]

by default the range of visible light is between 4000 and 7000

[@laughoutloud436]

Sir numericals me n-lambda aur n+lambda kab use karte hai? Sir please tell me

[@EngineeringPhysicsbySanjiv]

if you count n from 0 then use (2n+1)λ/2 and if you count n from 1 then use (2n-1)λ/2

[@laughoutloud436]

@@EngineeringPhysicsbySanjiv thank you sooo much sir!!

[@aabirchakraborty2031]

Sir , how is adding two times lambda /2 is equal to not adding lambda at all? Thank you sir for the lecture ☺️

[@EngineeringPhysicsbySanjiv]

When we add lambda/2 only once then there will be phase change of 180 degrees. When we add lambda/2 two times then the phase change will be 360 degrees which is equivalent to zero. So adding two times lambda /2 is equivalent to not adding lambda as there is no phase change introduced.

[@aabirchakraborty2031]

@@EngineeringPhysicsbySanjiv Thank you sir

[@asingh3009]

sir you have taken labmda(1) as 7000 A , why is it so?? (in last question) , what if we take 5000 A as lamda (1)

[@EngineeringPhysicsbySanjiv]

Use simple logic.. if n1 is smaller then lambda1 is larger.. check the two equations that we have written. These equations have left side same. So, for small value of n1, lambda1 should be more..

[@anandmule16]

Could you plz provide that pdf

[@EngineeringPhysicsbySanjiv]

Engineering Physics Notes links drive.google.com/file/d/1Ikw8Z0T6GRiRNnNOcjAK5Awprm0m9pXt/view?usp=drivesdk drive.google.com/file/d/1DK4jO1E-8qEojxkqHrDOwsefhAQ9iqkv/view?usp=drivesdk

[@itsmytube2133]

Why should not we use 2miut=nlambda

[@EngineeringPhysicsbySanjiv]

Because we need to use condition for maximum (strongly reflected)

[@shahbilal5094]

So long no videos 😭?

[@EngineeringPhysicsbySanjiv]

Started posting again..

[@aishwaryasrivastava2726]

Thank you sir 😃

[@EngineeringPhysicsbySanjiv]

Welcome