In a transformer ,when voltage decreases current increases. but this is a viola

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In a transformer ,when voltage decreases current increases.
but this is a violation of oms law.why?

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In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / adam

None of these answers seem to understand the apparent paradox. I am happy that transformers obey the law of conservation of energy; if the secondary voltage is double because Ns = 2 x Np then the maximum secondary current must be half of the primary current as VsIs cannot exceed VpIp.
Therefore there are circumstances when the circuit connected to the secondary end of the transformer will violate Ohm's law. This is true even if the a.c. version of ohm's law is used (that is inductance; 2(pi).f.L is included.
Now, why is this?
Can anyone explain?

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In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / jay

actully it depends on the power formula
i.e p=V*I*PF
so V=P/I*PF
so voltage is inversely proportional to current.
so when voltage increses current decreses.

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9 Yes

10 No

In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / meenakshi

ppl,Ohm's law is applicable only 4 those circuits which are
CONTAINING PURELY RESISTIVE ELEMENTS (NO INDUCTANCES OR
CAPACITANCES) for all forms of driving voltage or current,
regardless of whether the driving voltage or current is
constant (DC) or time-varying such as AC. At any instant of
time Ohm's law is valid for such circuits ONLY.

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3 Yes

4 No

In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / himanshu

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.

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In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / lijo joseph

If you take primary or secondary circuit individually, ohm's law holds at all instants....voltage inversely proportional to current is taken considering both the circuits together,ie, its a relation connecting primary and secondary....as per law of conservation of energy,input power and output power must be the same....

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In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / seshasainadh pudi

Ohmslaw
...in any conductor....i@v...
R=constant.... And...p@v...power is variable with respect to voltage.....
.....
....
In transformer....p=constant..
.power will not vary with voltage..

.that's why ohm's law is not is not applicable for transformer

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In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / arvind

How it is volation of the ohms law, please justify?
now according to me R=V/I, this is only ohms law.

Is This Answer Correct ?

9 Yes

11 No

In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / s.thambiraj

In transformer When Voltage decreases,power also
decreases.So Current also decreases.ie Power is directly
proportional to square of the voltage and current is
directly proportional to the power.ie power=(square of
voltage/Resistance).Now Current=Power/Voltage

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In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / hareesh

x-mer is constant power device

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In a transformer ,when voltage decreases current increases. but this is a violation of oms law.why?..

Answer / vishnu sharma

simple reason in transformer primary and secondary are not
connected electrically and also in primary,secondary the
current is same seperatelly

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2 No

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