Question

On what principle does the transformer work? State the following conditions for an ideal transformer:
(i) Leakage of magnetic flux
(ii) Resistance of primary coil
(iii) Resistance of secondary coil
(iv)Dissipation of power

Hint:

An ideal transformer assumes perfect energy transfer with no losses.

Answer 1

A transformer works on the principle of electromagnetic induction. 

Step 1: An alternating current in the primary coil creates a changing magnetic field. 

Step 2: This varying magnetic flux induces an EMF in the secondary coil according to Faraday's law. \[ V_s = \frac{N_s}{N_p} V_p \] \[ \boxed{\text{Transformer works on mutual induction.}} \] 

(i) Leakage of magnetic flux
Solution: There should be no flux leakage; all flux should link both coils. 

Step 1: Ideally, all magnetic flux produced by the primary coil should pass through the secondary coil. \[ \boxed{\text{Zero flux leakage for ideal transformer.}} \] 

(ii) Resistance of primary coilSolution: The primary coil should have zero resistance. 

Step 1: An ideal transformer assumes no resistive losses in the primary coil to prevent energy dissipation. \[ \boxed{\text{Zero resistance in the primary coil.}} \] 

(iii) Resistance of secondary coil
Solution: The secondary coil should also have zero resistance. 

Step 1: In an ideal transformer, the secondary coil is assumed to be perfect, with no resistance. \[ \boxed{\text{Zero resistance in the secondary coil.}} \] 

(iv) Dissipation of power 

Solution: 
There should be no power loss in an ideal transformer.
Step 1: In an ideal transformer, the entire power input is transferred to the output. Step 2: Efficiency is 100%, meaning no loss due to resistance, flux leakage, or core losses. \[ \boxed{\text{No power dissipation in ideal transformer.}} \]