# Ideal cells in parallel combination

#### saurabh tiwari

good evening to all
if two ideal cells with emf 6 volt and 3 volt are connected in parellel to supply current how the net emf can be decided

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#### cnh1995

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good evening to all
if two ideal cells with emf 6 volt and 3 volt are connected in parellel to supply current how the net emf can be decided
I think internal resistances must be given for parallel combination of cells..

#### saurabh tiwari

Thanks to all... It is same as best of my knowledge now i know that i am right [emoji6][emoji6]

#### phinds

Science Advisor
Gold Member
Thanks to all... It is same as best of my knowledge now i know that i am right [emoji6][emoji6]
And what is the conclusion that you "know is right" ?

#### saurabh tiwari

That it is impractical to say them ideal cell. Coz we ignore the internal resistance of a cell sometimes in comparison to external resistancesand call it ideal but when no external resistance is present you have to consider the internal resistance

#### phinds

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That it is impractical to say them ideal cell. Coz we ignore the internal resistance of a cell sometimes in comparison to external resistancesand call it ideal but when no external resistance is present you have to consider the internal resistance
Ah, yes. You are right, but ideal components are the staple of introductory electronics. and it is more correct to say that you simply cannot PUT ideal voltages sources with different voltages in parallel because you would thereby violate the definition of one or the other or both.

#### CWatters

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Just for completeness....

You can't connect two ideal current sources in series either.

#### saurabh tiwari

What is the problem in series combination

#### phinds

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What is the problem in series combination
cwaters said ideal CURRENT sources cannot be put in series. Again, it would violate the definition of one or the other or both (unless they had identical values, in which case it's just silly)

#### saurabh tiwari

Is there any problem in this solution

#### phinds

Science Advisor
Gold Member
No problem, since ideal voltage sources can go in series (and ideal current sources can go in parallel)

Ok ok got it

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