Advertisements
Advertisements
प्रश्न
Explain why an induced current must flow in such a direction so as to oppose the change producing it.
Advertisements
उत्तर
So that the mechanical energy spent in producing the change, is transformed into the electrical energy in form of induced current.
APPEARS IN
संबंधित प्रश्न
Derive an expression for e.m.f. and current in terms of turns ratio
What type of current is transmitted from the power station?
Devices which is used to convert high alternating current to low alternating current is ______.
A step-down transformer connected to the main supply of 220 V is used to operate 11V,88W lamp. Calculate
- Voltage transformation ratio and
- Current in the primary
The output power in step-up transformer used in practice is ______.
A 220 V input is supplied to a transformer. The output circuit draws a current of 2.0 A at 440 V. If the ratio of output to input power is 0.8, then the current drawn by primary winding 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 magnetic flux through a coil perpendicular to its plane is varying according to the relation Φ = (5t3 + 4t2 + 2t - 5) Weber. If the resistant of the coil is 5 ohm, then the induced current through the coil at t = 2 sec will be ______.
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.
