1. A series resonant circuit implies
- zero PF and maximum current
- unity PF and maximum current
- unity PF and minimum current
- zero PF and maximum current
2. DC generator works on the principle f
- fleming’s lefthand rule
- Fleming’s righthand rule
- lenz’s law
- none of the above
3. EMF induced in each conductor of a dc machine is
- an alternating emf
- a direct emf
- pulsating emf
- emf of random waveform
4. In large dc generators, the magnetic field is produced by
- permanent magnet
- electromagnet
- either a or b
- none of the above
5. The emf generated y a dc generator may be increased by increasing
- speed of rotation
- excitation
- armature length
- either a or b
6. If we increase field current of a dc generator, its emf output
- increases indefinitely
- increases till the winding burns
- increases till the magnetic saturation takes place
- first increases and then reducing
7. The terminal voltage of a dc shunt generator on loading
- increases slightly
- decreases slightly
- decrease sharply
- remains constant
8. The transformer action requires a
- constant magnetic flux
- increasing magnetic flux
- alternating magnetic flux
- alternating electric flux
9. The induced emf in a transformer depends on
- frequency
- number of turns
- maximum value of flux
- all of the above
10. The flux in transformer core
- increases with load
- decreases with load
- remains constant irrespective of load
- none of the above