Home
Class 12
PHYSICS
A transformer is used to light a 100W an...

A transformer is used to light a 100W and 110V lamp from 220V mains. If the main current is 0.5 amp, fhe efficiency of the transformer is approximately:

A

0.96

B

0.9

C

0.99

D

0.95

Text Solution

Verified by Experts

Promotional Banner

Topper's Solved these Questions

  • MODEL QUESTION PAPER 4

    SARAS PUBLICATION|Exercise EXERCISE|42 Videos

  • MODEL QUESTION PAPER 6

    SARAS PUBLICATION|Exercise EXERCISE|45 Videos

Similar Questions

Explore conceptually related problems

A transformer connected to 220 V mains is used to light a lamp of rating 100 W and 110 V. If the primary current is 0.5 A, the effeciency of the transformer is (approximately)

A transformer is used to light a 140 W, 24 V bulb from a 240 V AC mains. The current in the main cable is 0.7 A. find the efficiency of the transformer.

A step down transformer convert a voltage of 2200 V into 220V in the transmission line. Number of turns in the primary coil is 5000. Efficiency of transformer is 90% and its output power is 8kW. Calculate (i) the number of turns in the secondary coil, (ii) input power.

A 110 W, 220 V bulb draws a current

A step-down transfomer reduces the supply voltage from 220 V to 11 V and increase the current from 6 A to 100 A. Then its efficiency is

A transformer having efficiency of 90% is working on 200 V and 3 kW power supply.If the current in the secondary coil is 6 A, the voltage across the secondary coil and the current in the primary coil respectively are

SARAS PUBLICATION-MODEL QUESTION PAPER 5-EXERCISE
  1. Four identical cells of emf e and internal resistance r are to be conn...

    Text Solution

    |

  2. A parallel plate capacitor is charged and then isolated. The effect of...

    Text Solution

    |

  3. A spherical shell, of radius 10 cm is carrying a charge g. If the elec...

    Text Solution

    |

  4. Three point charges 3nC, 6nC and 9nC are placed at the corners of an e...

    Text Solution

    |

  5. In the circuit shown below, the ammeter and the voltmeter readings are...

    Text Solution

    |

  6. Two cells of emf E1 and E2 are joined in opposition (such that E1>E2)....

    Text Solution

    |

  7. If the velocity of light in a medium is 2.25 xx 10^(8) ms^(-1) then th...

    Text Solution

    |

  8. Two concentric coils each of radius equal to 2pi cm are placed at righ...

    Text Solution

    |

  9. The resistance of a bulb filament is 100 Omega at a temperature of 100...

    Text Solution

    |

  10. In Wheatstone network, P=2Omega,Q=2 Omega,R=2Omega and S = 3 Omega. Th...

    Text Solution

    |

  11. Core of electro magnets are made of ferromagnetic material which has:

    Text Solution

    |

  12. If there is no torsion in the suspension thread, then the time period ...

    Text Solution

    |

  13. Two parallel wires 1 m apart carry currents of 1A and 3 A respectively...

    Text Solution

    |

  14. A galvanometer of resistance 50 Omega gives a full scale deflection fo...

    Text Solution

    |

  15. A cyclotron is used to accelerate:

    Text Solution

    |

  16. A transformer is used to light a 100W and 110V lamp from 220V mains. I...

    Text Solution

    |

  17. In an LCR series circuit, at resonance

    Text Solution

    |

  18. An aircraft with a wingspan of 40 m flies with a speed of 1080 km//h i...

    Text Solution

    |

  19. Two coils have amutual inductance 0.005 H. The current changes in the ...

    Text Solution

    |

  20. The magnetic susceptibility of a paramagnetic material at -73 ^@ C is ...

    Text Solution

    |