Is a transformer following ohm's law?

AI Thread Summary
Transformers do not violate Ohm's law, as the law applies to resistive loads rather than the transformer itself. When voltage is increased in a transformer, current decreases proportionally, maintaining the relationship dictated by Ohm's law when applied to both primary and secondary circuits. For example, applying 100 volts to a 10:1 transformer results in 10 volts on the secondary side, with corresponding changes in current. Misunderstandings often arise from incorrectly applying Ohm's law to the transformer as a whole instead of to its individual circuits. Overall, Ohm's law remains valid when analyzing the behavior of electricity through resistive loads connected to the transformer.
srishankar18
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According to ohm's law voltage is directly proportional to current that is if voltage get increased current also should get increased but in a transformer if voltage get increased current get decreased.

so, Is a transformer is obeying ohm's law or not
 
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You are not applying ohms law to the transformer correctly when stated the way you have. If you apply 100 volts to a 10:1 transformer you will end up with 10 volts out. If you put a 10 ohm resistor on the secondary you will have one ampere passing through the resistor. In an ideal transformer the 100 volt source will be sourcing .1 amps. Increase the primary voltage by a factor of 2 and the secondary voltage will increase by the same. The amps in both windings will increase by a factor of 2 as well. Ohms law has not been violated.
 
To put it another way, Ohms law is for determining the behavior of electricity through a load (a resistor). A transformer by itself is not a load.

We see people make this mistake a lot (that's 3 times in 3 days) and I don't know why...
 
Yep. Remember that Ohm's law only applies for Ohmic devices (which obey Ohm's law and hence named thus).

(Seriously, I'm not trying to be smart or patronising here.)
 
You apply Ohms law separately to the primary circuit and to the secondary circuit of a transformer. You do not use Ohms law to learn how the primary induces current in the secondary.
 
Thanks

Thanks a lot to every body who had taken care for replying this thread.

I've got some information from your answers.

Thank you ...:smile:
 
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