Circuit Breaker Objective Type Questions and answers

6.  Circuit breakers usually operates under

   A. Transient state of short circuit current

   B. Sub transient state of short circuit current

   C. Steady state of short circuit current

   D. After DC component has ceased

7.  The voltage appearing across the contacts after opening of the circuit breaker is called..............voltage

   A. Recovery

   B. Surge

   C. Operating

   D. Arc

8.  In a circuit breaker the basic problem is to

   A. Maintain the arc

   B. Extinguish the arc

   C. Transmit large power

   D. Emit the ionizing electrons

9.  The arc voltage produced in ac circuit breaker is always

   A. In phase with arc current

   B. Legging the arc current by 90^o

   C. Leading the arc current by 90^o

   D. None of the above

10.  In railway applications............circuit breaker is used

   A. Sf₆

   B. Bulk oil

   C. Minimum oil

   D. Air brake

< 1 2 3 4 5 6 7 8 9 10 Next>