English
Tamil Nadu Board of Secondary EducationHSC Science Class 12

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

Advertisements
Advertisements

Question

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

Options

  • 1.2

  • 0.83

  • 0.12

  • 0.9

MCQ
Advertisements

Solution

0.83

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Electromagnetic Induction And Alternating Current - Evaluation [Page 259]

APPEARS IN

Samacheer Kalvi Physics - Volume 1 and 2 [English] Class 12 TN Board
Chapter 4 Electromagnetic Induction And Alternating Current
Evaluation | Q I. 8. | Page 259

RELATED QUESTIONS

A power transmission line feeds input power at 2200 V to a step-down transformer with its primary windings having 300 turns. Find the number of turns in the secondary to get the power output at 220 V.


State the principle of transformer working with the help of a diagram


For what purpose are the transformers used? Can they be used with a direct current source?


What is the function of a step-up transformer?


The primary of a transformer has 40 turns and works on 100 V and 100 W. Find a number of turns in the secondary to step up the voltage to 400 V. Also calculate the current in the secondary and primary.


Eddy currents in the core of transformer can't be developed by ______.

For an ideal step-down transformer, the quantity which is constant for both the coils is ______.


Read the following paragraph and answer the question:


Long distance power transmissions

The large-scale transmission and distribution of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped up. It is then transmitted over long distances to an area sub-station near the consumers. There the voltage is stepped down. It is further stepped down at distributing sub-stations and utility poles before a power supply of 240 V reaches our homes.

Which of the following statement is true?


The large scale transmission of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped-up because of ______.


The primary coil of a transformer has 60 turns whereas its secondary coil has 3000 turns.

If a current of 5A flows in the primary coil, how much current will flow in a load in the secondary coil? State the assumption you have made regarding the transformer, in this calculation.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×