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sarthak321 (62)

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 given the following L-R circuit...


 


A battery of emf E is connected in series with a resistance R and inductor coil with inductance L...


 


now if i current flows through it then using kirchoff's law


E - iR -  L(di/dt) = 0


 


and also gien di/dt = 5 A/s


 


question if we solve the eqn we'll always find the value of i to be same....however we are given di/dt=5A/s...


 


i.e the current is increasing at 5 A per second....


 


but the above equation gives constant value of i....


 


justify...........


ratings ensured........... ( mail me to know the answer)...



    
bhaskaryya (559)

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in dis case, we use inductor vich will oppose increase in emf. simply take d example, whn we switch on an ac circuit ( in household circuits),,, emf increases wid increases in time. but whn we use inductor in d circuit, self inductance is produced in it vich will try to oppose d effect of increase in emf  i.e.  in sinusoidal graph of emf , it will always remain const. there4 current is also const.


     as u r askin y I is const. though it is given as 5 A/s i.e. it changes, then i wud like to tell u dat, d increase in emf will try to increase d current at const rate,,,,but as self inductance produced in d inductor, it will prevent d effect of increase in current( or emf),,,, so we get always a const. current.


     if i m correct rate me,,,,,,otherwse tell me...........

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sarthak321 (62)

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 i dont really think u have answered correctly since the di/dt which is given includes the effect of the inductor and so does the final current which flows through it....


and even if u are correct and constant current flows due to  the inductor what is the need to derieve a complex expression like



we could directly say the current is constant and would remain constant and is independent of the time....


 

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sarthak321 (62)

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 so nobdies got guts to answer

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bhaskaryya (559)

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cn u plz put d ans in expanded form.........help us in knowing d ans.......

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