Answer / nishant

due 2 magnetostriction

Answer / kowsar shaik

Transformer noise is caused by a phenomenon called
magnetostriction.if a piece of magnetic steel sheet is
magnetized it will extend itself.A transformer is
magnetically excited by an alternating voltage and current
so that it becomes extended and contracted twice during a
full cycle of magnetizationThis extension and contraction
is not uniform, consequently the extension and contraction
varies all over a sheet.so noice forms in all sheets of tf.

Answer / kalidass

While giving the ac power to the transformer the core will
compress and elongation. Due to this noise is come.

Answer / er. rinku

mostly transformers r making noise during its runing
conditions bcoz transformers operate at high frequence due
to this reason the size of the core changes and trasformers
makes a humming sound

Answer / sreenath

due to electrostriction,there is a uneven extension and
constraction in transformer core due to this transformer
subjected to noise

Answer / praful nandankar

The magnetic core elongates and contracts due to the effect
of magnetostriction as the input to the transformer is ac .








praful nandankar

Answer / khyber faqir

when we hear a sound from a transformer it means there is
conversion of energy from one form to ohter form .
core losses are devided into tow components in a
transformer
1-eddy current loss :that cause the transformer to be
heated
2-hysteresis loss that cause the transformer to produce a
sound.

Answer / devender sangwan

due to the presence of third harmonics present in the ac input supply.

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