Home
Class 12
PHYSICS
The armature of a dc motor has 20 Omega ...

The armature of a dc motor has `20 Omega` resistance It draws a currrent of `1.5` A when run by a `220 V` dc supply The value of the block emf induced in it is .

A

150 V

B

170 V

C

180 V

D

190 V

Text Solution

Verified by Experts

The correct Answer is:
D
Promotional Banner

Topper's Solved these Questions

  • ELECTROMAGNETIC INDUCTION

    DISHA PUBLICATION|Exercise EXERCISE - 2 : Concept Applicator|29 Videos
  • ELECTROMAGNETIC INDUCTION

    DISHA PUBLICATION|Exercise EXERCISE - 2 : Concept Applicator|29 Videos
  • ELECTRIC CHARGES AND FIELDS

    DISHA PUBLICATION|Exercise Exercise - 2 : Concept applicator|24 Videos
  • ELECTROMAGNETIC WAVES

    DISHA PUBLICATION|Exercise Exercise - 2 : Concept Applicator|30 Videos

Similar Questions

Explore conceptually related problems

The armature of a DC motor has 20Omega resistance. It draws a current of 1.5 A when run by 200 V DC supply The value of back emf induced in it will be

The armature of dc motor has 20Omega resistance. It draws current of 1.5 ampere when run by 220 volts dc supply. the value of back e.m.f. induced in it will be

The resistance of the armature of an electric motor is 55 ohm. The motor draw a current of 2 A when running at 220 V. What is the back e.m.f ?

A d.c motor has internal resistance 4 ohms . It is operated at 220 volts and draws 5 ampere current . The useful mechanical power developed is :-

A series battery of 6 lead accumulators each of emf 2.0V and internal resistance 0.50Omega is charged by a 10V d.c. supply. What series resistance should the used in the charging circuits in order to limit the current to 8.0A? Using the required resistor, obtain (a) the power supplied by the d.c. source (b) the power supplied by the d.c. energy stored in the battery in 15min.

A battery is formed by connecting three cells in series . The emfs of cells are 5 V, 2.5 V and 1.5 V and their internal resistance are 0.5 Omega ,0.05 Omega and 0.45 Omega respectively. This battery is connected across a load resistance of 5 Omega what current will be supplied by the battery ? if the cell of emf 1.5 V were connected with reverse polarity then what would have been the current supplied by the battery ?

An electric motor operating on a 60 V dc supply draws a currrent of 10A . If the effeciency of the motor is 50% , the resistance of its winding is

An electric motor runs a D.C. source of e.m.f. 200 V and draws a current of 10A . If the efficiency is 40% , then ressistance of the armature is:

A simple electric motor has an armature resistance of 1Omega and runs from a dc source of 12 volt . When running unloaded it draws a current of 2 amp . When a certain load is connected , its speed becomes one-half of its unloaded value . The new value of current drawn

DISHA PUBLICATION-ELECTROMAGNETIC INDUCTION -EXERCISE - 1 : Concept Builder
  1. Two circular coils can be arranged in any of the three situations show...

    Text Solution

    |

  2. Two coils, one primary of 500 turns and one secondary of 25 turns, are...

    Text Solution

    |

  3. Two circular coils, one of smaller radius r(1) and the other of very l...

    Text Solution

    |

  4. A long solenoid has 500 turns. When a current of 2A is passed through ...

    Text Solution

    |

  5. A metal disc of radius 100 cm is rotated at a constant angular speed o...

    Text Solution

    |

  6. A copper disc of radius 0.1 m rotates about its centre with 10 revolut...

    Text Solution

    |

  7. A square loop of side a is rotating about its diagonal with angular ve...

    Text Solution

    |

  8. A wire loop is rotated in a uniform magnetic field about an an axis pe...

    Text Solution

    |

  9. In an A.C. generator, when the plane of the armature is perpendicular ...

    Text Solution

    |

  10. The pointer of a dead-beat galvanometer gives a steady deflection beca...

    Text Solution

    |

  11. If a coil made of conducting wires is rotated between poles pieces of ...

    Text Solution

    |

  12. The armature of a dc motor has 20 Omega resistance It draws a currrent...

    Text Solution

    |

  13. When a metallic plate swings between the poles of a magnet

    Text Solution

    |

  14. A generator has an e.m.f. of 440 Volt and internal resistance of 4000 ...

    Text Solution

    |

  15. An AC generator of 220 V having internal resistance r=10 Omega and ext...

    Text Solution

    |

  16. A six pole generotar with fixed field excitation developes an e.m.f. o...

    Text Solution

    |

  17. The number of turns in the coil of an ac genrator is 5000 and the area...

    Text Solution

    |

  18. plane of eddy currents make an angle with the plane of magnetic lines ...

    Text Solution

    |

  19. The back emf in a DC motor is maximum when,

    Text Solution

    |

  20. A series would dc motor has a total resistance of 1.5 ohm. When connec...

    Text Solution

    |