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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.
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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