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प्रश्न
A transformer is used to step up an alternating emf of 200V to 440V. If the primary coil has 1000 turns, calculate the number of turns in the secondary coil.
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उत्तर
This is an example of step-up transformer
`n_s/n_p = V_s/V_p`
`therefore n_s/1000 = 440/200`
`therefore n_s = 2200 "turns"`
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