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प्रश्न
A power transmission line feeds input power at 2200 V to a step-down transformer with its primary windings having 300 turns. Find the number of turns in the secondary to get the power output at 220 V.
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उत्तर
ns= ?
np= 3000
Ep= 2200 V
ES= 220 V
Since,
`E_s/E_p= n_s/n_p`
`220/2200= n_s/3000`
`n_s = 300`
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