Home
Class 12
PHYSICS
A transformer with efficiency 80% works ...

A transformer with efficiency `80%` works at `4 kW` and `100 V`. If the secondary voltage is `200 V`, then the primary and secondary currents are respectively

A

40 A, 16 A

B

16 A, 40 A

C

20 A, 40 A

D

40 A, 20 A

Text Solution

Verified by Experts

The correct Answer is:
A
`P_(P)=I_(P)*e_(P)`
`I_(P)=(P_(P))/(e_(P))=(4xx10^(3))/(100)=40A`
`eta=(P_(S))/(P_(P))=(I_(S)e_(S))/(P_(P))`
`I_(S)=(eta*P_(P))/(P_(P))=(0.8xx4xx10^(3))/(200)=16A`
Promotional Banner

Topper's Solved these Questions

  • ELASTICITY

    NIKITA PUBLICATION|Exercise MCQ|314 Videos

  • ELECTRONS AND PHOTONS

    NIKITA PUBLICATION|Exercise MCQs|162 Videos

Similar Questions

Explore conceptually related problems

A transformer has an efficiency of 80%. It works at 4 kW, 100 V. If the secondary voltage is 240 V, Calculate the primary and secondary currents.

A transformer has an efficiency of 80%. It works at 4 kW and 100 V. If secondary voltage is 240 V, the current in primary coil is

A transformer has an efficiency of 80% and works at 100 volt and 4 kw. If the secondary voltage is 240 V. The current in secondary is

A transormer has an efficiency of 80%. It is connectes to a power input of 5 kW at 200 V. It the secondary voltage is 250 V, the primary and secondary currents are respectively

A transformer has an efficiency of 80%. It delivers 2kW output power at 100 V primary and 240 V secondary voltages. Calculate primary and secondary currents

The efficiency of a transformer is 98%. The primary voltage and current are 200 V and 6A . If the secondary voltage is 100 V , the secondary current

A transformer of efficiency 90% has turns ratio 10 : 1. If the voltage across the primary is 220 V and current in the primary is 0.5 A, then the current in secondary is

A transformer having efficiency of 80% is working on 200 V and 2 kW power supply. If the current in the secondary coil is 8A, the voltage across the secondary coil and the current in the primary coil respectively are

NIKITA PUBLICATION-ELECTROMAGNETIC INDUCTION-MCQs
  1. The turn ratio of a transformers is given as 2:3. If the current throu...

    Text Solution

    |

  2. Core of transformer is made up

    Text Solution

    |

  3. A transformer with efficiency 80% works at 4 kW and 100 V. If the seco...

    Text Solution

    |

  4. In a step up transformer, if ratio of turns of primary to secondary is...

    Text Solution

    |

  5. A step-down transformer is used on a 1000 V line to deliver 20A at 120...

    Text Solution

    |

  6. Alternating currents can be produced by a

    Text Solution

    |

  7. An emf induced in a coil rotating in a uniform magnetic field is given...

    Text Solution

    |

  8. The maximum value of emf indued in a coil rotating in a uniform magnet...

    Text Solution

    |

  9. The alternaing current of equivalent value of I(0)//sqrt(2) is

    Text Solution

    |

  10. The peak value of the a.c. current flowing throw a resistor is given b...

    Text Solution

    |

  11. Alternating current can be measured with the help of

    Text Solution

    |

  12. D.C. ammeter is connected in a circuit through which an a.c. emf of 50...

    Text Solution

    |

  13. The r.m.s. value of an alternating current is

    Text Solution

    |

  14. The maximum value of A.C. emf in a complete cycle is

    Text Solution

    |

  15. A voltmeter reads V volts in an A.C. circuit then V is

    Text Solution

    |

  16. AC measuring instruments measures

    Text Solution

    |

  17. In an AC circuit, the mass value of the current I("rms") is related to...

    Text Solution

    |

  18. If an AC ammeter reads I A in an AC circuit, then the peak value of th...

    Text Solution

    |

  19. The average value of alternating current over a complete cycle ...

    Text Solution

    |

  20. Alternating current can not be measured by D.C. Ammeter because

    Text Solution

    |