Home
Class 10
PHYSICS
A transformer inside the power supply fo...

A transformer inside the power supply for a portable CD player has 500 turns in the primary coil. It supplies an emf of amplitude 6.8 V when plugged into the usual sinusoidal household emf of amplitude 170 V. (a) How many turns does the secondary coil have? (b) If the current drawn by the CD player has amplitude 1.5 A, what is the amplitude of the current in the primary?

Text Solution

Verified by Experts

a) The turns ratio is equal to the emf ratio
`E_2/E_1 = N_2/ N_1`
` rArr N_2 = N_ 1 E_2/E_1 = (6.8)/(170) xx 500 = 20` turns
(b) The current is inversly proportional to the emf
` I_1/I_2 = E_2/E_1 = N_2/N_1`
` rArr I_1 = E_2/E_1 I_2 = (6.8)/(170) xx 1.5 = 0.060 A`
Promotional Banner

Topper's Solved these Questions

  • ELECTROMAGNETIC INDUCTION

    CENGAGE PHYSICS|Exercise OLYMPIAD AND NTSE LEVEL EXERCISES|10 Videos
  • ELECTROMAGNETIC INDUCTION

    CENGAGE PHYSICS|Exercise MANDATORY EXERCISE (EXERCISE SET IV)|1 Videos
  • CURRENT ELECTRICITY

    CENGAGE PHYSICS|Exercise OLYMPIAD AND NTSE LEVEL EXERCISES|10 Videos
  • ELECTROMAGNETIC SPECTRUM AND RADIATIONS

    CENGAGE PHYSICS|Exercise Olympiad And NTSE Level Exercises|10 Videos

Similar Questions

Explore conceptually related problems

The average emf induced in the secondary coil is 0.1 V when the current in the primary coil changes from 1 to 2A in 0.1 s .What is the mutual inductance of the coils.

A transformer has 200 turns in primary coil and 1000 turns in secondary. The induced voltage in secondary when primary is supplies with 150 V DC supply is:

A transformer has 100 turns in the primary coil and carries 8A current. If input power is one kilowatt, the number of turns required in the secondary coil to have 500V output will be

A transformer whose efficiency is 90%, draws 5 A when 200 V is applied to its primary coil. If output is drawn at 300 V, what is the current in secondary coil ? If number of turns in primary coil is 500, what is the number of turns in secondary coil?

In a stepup transformer, the ratio of number of turns in primary and secondary coils is 1 : 10 . What voltage will develop in the secondary if the primary is connected to 220 V mains ? If the current drawn from the secondary is 2A, calculate the current through the primary

A small loop of area 3.1 m m^(2) is placed inside a long solenoid that has 672 turns/cm and carries a sinusoidally varying current i of amplitude 1.28 A and angular frequency 212 rad/s. The central axes of the loop and solenoid coincide. What is the amplitude of the emf induced in the loop?

A power transformer (step up) with an 1:8 turns ratio has 60 Hz,120 V across the primary, the load in the secondary is 10^(4) Omega .The current in the secondary is

A generator supplies 100 V to the primary - coil of a transformer of 50 turns.If the secondary coil has 500 turns, then the secondary voltage is