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Question
Explain step up and step down transformer?
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Solution
- Step-up transformer:
a. A transformer that converts a low voltage at high current into a high voltage at low current is called a step-up transformer.
b. In a step-up transformer, the number of turns in secondary coil NS is greater than the number of turns in primary coil NP. In this transformer, eS > eP and IS < IP.
c. The primary coil is made from a thick insulated copper wire so that it can sustain the high current. The secondary coil is made of a thin insulated wire.
d. Current through secondary is less than primary. - Step down transformer:
a. A transformer which converts a high voltage at low current into a low voltage at high current is called a step-down transformer.
b. In step down transformer, the number of turns in the secondary coil NS is less than the number of turns in the primary coil NP. In this transformer eS < eP and IS > IP.
c. The primary coil is made of a thin insulated wire and the secondary coil is made from thick wire so that it can sustain the high current.
d. Current through primary is less than secondary.
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