Correct answer : c.change the output voltage.
A transformer is an electrical gear box, much like an auto transmission, used to change the ratio of potential energy(voltage or torque) to kinetic energy(current or rpm) . That ratio is called impedance or resistance. It is also useful for circuit isolation.
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Electrical power distribution systems use transformers to convert their power to high voltage so that the power line wire resistance power losses are minimized, and convert back to a lower voltage at the customer site. Transformers only work with AC current and they are the reason Edison's DC power system lost to Tesla and Westinghouse.
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A transformer changes voltage by means of mutual electromagnetic induction. The electrical current running through the primary coil/circuit is used to create a magnetic field. Changes in the current will result in changes in the magnetic field, which in turn will alter the voltage of the secondary coil/circuit.
A transformer is a device for changing the voltage of electricity. In popular use, it refers to the type of transformer that steps high voltage electricity down to the level necessary for domestic use.
[1] Increase ac voltage.
[2] Decrease ac voltage.
[3] Increase current by changing from high voltage into low voltage.
[4] Coupling uses in RF, IF , AF between two stages.
[5] Matching the impedance between two devices or stages.
[6] Use in Oscillating circuit.
(a) Correct !
(b) Wrong, transformer has lagging power.
(c) Correct !
(d) Correct !
(a) yes, a welding transformer primary many turns secondary one turn, produce higher current for welding
(b) no, only capacitor will improve pf of RL load
(c) yes, it will change the voltage to your requirements
(d) how??? are we talking about matching impedance? like connecting two tv coax cable to a one coax cable source, in dollar store, you can buy this little gadget
(others) in a class-2 circuit, the transformer is designed to limit the current flow when the transformer secondary is shorted, i also used transformer for safety isolation purpose
Step up & Step Down Function without wastage of power .Step up for Transformer Used in power Plant to Step up to Extra High Voltage for Long Distance Transmission. Same Extra High voltage is step down to Utility purpose. Transformer used for Making Isolating Power for Safer use. example for Various Instrumental purpose,& many more application. Without Transformer Electricity utility very difficult task.
Transformer, electrical device used to transfer an alternating current or voltage from one electric circuit to another by means of electromagnetic induction induction .
a transformer basically transforms an alternating voltage from one value to another i.e greater or smaller
I jus need to know the main purpose
