a) Not run b) Burn due to extraordinarily high potential building up in the armature c) Not build up any voltage d) Run under unstable operating conditions. Ans: (c)
a) Armature flux due to armature current b) Load current c) Shunt and series field current d) None of these Ans: (a)
a) Makes the current distribution at brushes equal to avoid sparks b) Helps the noiseless operation of the machine c) Provides a path for the circulation of unbalanced current d) Provides mechanical strength for the winding of the armature Ans: (a)
a) Armature resistance drop b) Armature reaction c) Decrease in field current d) All of then Ans: (d)
a) Shunt coil may be connected in reverse direction b) There is no resistance magnetism in the poles c) Its shunt field resistance is more than critical resistance d) Any one of the above Ans: (d)
a) Greater reliabilty b) Greater efficiency c) Meeting more load demands d) All of these Ans: (d)
a) Internal characteristic b) No load saturation characteristic c) Both (a) and (b) d) None of these Ans: (c)
a) D.C. machines b) A.C. machines c) Universal machines d) All of these Ans: (d)
a) Series generator b) Shunt generator c) Compound generator d) Any one of then Ans: (b)
a) Take a smaller shunt of the total load b) Run as the motor in the same direction c) Take a large share of the total load d) Run in the opposite direction as motor Ans: (b)
a) At which it develops maximum voltage b) At which it supply maximum power c) Beyond which it can not develop any voltage d) At which the speed of generator is infinity Ans: (c)
a) Decrease b) Increase c) Remain same d) None of these Ans: (b)