Advertisements
Advertisements
प्रश्न
What is the function of a transformer in an a.c. circuit? How do the input and output powers in a transformer compare?
Advertisements
उत्तर
A transformer is a device by which the amplitude of an alternating e.m.f. can be increased or decreased.
For an ideal transformer, when there is no loss of energy, the output power is equal to input power i.e.,
Power in secondary coil = power in primary coil
ESLS = EPLS
संबंधित प्रश्न
Derive an expression for e.m.f. and current in terms of turns ratio
Express the turn ratio in terms of voltages.
You are required to make an electromagnet from a soft iron bar by using a cell, an insulated coil of copper wire and a switch. (a) Draw a circuit diagram to represent the process. (b) label the poles of the electromagnet.
A transformer is used to step up an alternating emf of 200V to 440V. If the primary coil has 1000 turns, calculate the number of turns in the secondary coil.
Why is the core of a transformer made of soft iron?
A transformer having efficiency of 80% is working on 200 V and 6 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 ____________.
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 ______.
Derive the equation for a transformer.
A 12 V, 60 W lamp is connected to a 220 V AC supply using an ideal transformer. Find the primary current.
A step down transformer connected to an AC mains supply of 220 V is made to operate at 11 V, 44 W lamp. Ignoring power losses in the transformer, what is the current in the primary circuit?
