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प्रश्न
For what purpose are the transformers used? Can they be used with a direct current source?
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उत्तर
The purpose of the transformer is to step up or step down the a.c. voltage.
No, a transformer cannot be used with a direct current source.
संबंधित प्रश्न
How much current is drawn by the primary of a transformer connected to 220 V supply when it delivers power to a 110 V − 550 W refrigerator?
Name two factors on which the magnitude of an induced e.m.f. in the secondary coil depends.
State the underlying principle of a transformer. How is the large scale transmission of electric energy over long distances done with the use of transformers?
What is a transformer? On what principle does it work?
State whether true or false. If false, correct the statement.
A transformer can step up direct current.
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
1 MW power is to be delivered from a power station to a town 10 km away. One uses a pair of Cu wires of radius 0.5 cm for this purpose. Calculate the fraction of ohmic losses to power transmitted if
- power is transmitted at 220 V. Comment on the feasibility of doing this.
- a step-up transformer is used to boost the voltage to 11000 V, power transmitted, then a step-down transfomer is used to bring voltage to 220 V. (ρCu = 1.7 × 10–8 SI unit)
An iron rod is placed parallel to magnetic field of intensity 2000 Am-1. The magnetic flux through the rod is 6 × 10−4 Wb and its cross-sectional area is 3 cm2. The magnetic permeability of the rod in Wb A-1m-1 is ______.
An ideal transformer converts 170 V a.c. to 1.70 KV a.c. to transmit a power of 3.4 KW. If primary coil has 500 turns then alternating current in secondary coil is ______.
