Advertisements
Advertisements
प्रश्न
State two ways through which the strength of an electromagnet can be increased.
Advertisements
उत्तर
the strength of an electromagnet can be increased by following ways:
(i) By increasing the number of turns of winding in the solenoid.
(ii) By increasing the current through the solenoid.
संबंधित प्रश्न
State two factors on which the magnitude of induced e.m.f. depend.
Explain the significance of Lenz’s law to show the conservation of energy in electromagnetic induction.
What is the function of a transformer in an a.c. circuit? How do the input and output powers in a transformer compare?
What is a transformer? On what principle does it work?
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.
We need to step-up the voltage for power transmission, so that ______.
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?
Draw the effective equivalent circuit of the circuit shown in figure, at very high frequencies and find the effective impedance.

Efficiency of transformer is the ratio of ______.
What are the three main components of a transformer?
Which law relates the changing flux to the EMF induced in both coils?
