Answer / dileep gopalakrishnan

in case of air circuit breaker the Arc quenching medium
between fixed & moving contacts is air...air at high velocity
is passed between two contacts at the time of CB opening thus
arc is removed...In case of Vacuum circuit breaker two
contacts are placed in vacuum bottles...so no electron flow occurs in vacuum becoz no media to conduct electricity...

Answer / dileep gopalakrishnan

in case of air circuit breaker the Arc quenching medium
between fixed & moving contacts is air...air at high velocity
is passed between two contacts at the time of CB opening thus
arc is removed...In case of Vacuum circuit breaker two
contacts are placed in vacuum bottles...so no electron flow occurs in vacuum becoz no media to conduct electricity...

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