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why dc current is not used in transformer. state law of thermodynamics

flux should be produced in the primary winding and secondary winding of the transformer to work the transformer.

from the faraday's law we know flux will produced if there is change in current in the gap of wire coil.

in ac current only the current changes with time where as dc current value does not change always with tome. so dc current not be used in transformer ac current should be used.

for law of thermodynamics go through any book of thermodynamics. you may go through the book written by Khurmi.

Originally Posted by Unregistered

why dc current is not used in transformer. state law of thermodynamics

there are four laws of THERMODYNAMICS

The zeroth law of thermodynamics, which underlies the basic definition of temperature.

The first law of thermodynamics, which mandates conservation of energy, and states in particular that the flow of heat is a form of energy transfer.

The second law of thermodynamics, which states that the entropy of an isolated macroscopic system never decreases, or (equivalently) that perpetual motion machines are impossible.

The third law of thermodynamics, which concerns the entropy of a perfect crystal at absolute zero temperature, and which implies that it is impossible to cool a system all the way to exactly absolute zero.

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Originally Posted by Unregistered

why dc current is not used in transformer. state law of thermodynamics

we don't use dc current in transformer because

Transformer are passive devices thattransform AC to AC by magnetics and coupling. DC IS UNIDIRECTIONAL it does not change POLARITY. While it is possible to saturate a transformer primary it output cannot reflect the change since it has reached steady state

hi!

There are 2 laws of thermodynamics:

First Law of Thermodynamics: "Energy can be changed from one form to another, but it cannot be created or destroyed." The total amount of energy and matter in the Universe remains constant, merely changing from one form to another.

The Second Law of Thermodynamics: "in all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state." This is also commonly referred to as entropy.

Reason for not using DC current in transformer:
Transformers only work on AC. AC going through one coil produces an alternating magnetic field which induces a current in the other coil.

If you put DC into one coil of a transformer, it will produce only a steady magnetic field, which will have no effect on the other coil.

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why we need reactive power

reactive power is necessary for any applications?

what is dc

why do we prefer shaft motors for eee lab ? y shouldn't we go for other motor?

1.electrons in conductors actually they move from negatve pole to positive pole or they align in one direction under effect of electric field?
2.do capacitor store charge in the same way as batteries?
3.do electical charge behave as energy?
4.do ac current obey ohms law?

do capacitors store charge in the same way as batteries?

Dc current have no polarity change,why

flux should be produced in the primary winding and secondary winding of the transformer to work the transformer.

from the faraday's law we know flux will produced if there is change in current in the gap of wire coil.

in ac current only the current changes with time where as dc current value does not change always with tome. so dc current not be used in transformer ac current should be used.

for law of thermodynamics go through any book of thermodynamics.

Good luck...........

what is not change in dc transformer?

if dc current does not change with time what effect on dc transformer