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प्रश्न
A circular coil carrying a current I has radius R and number of turns N. If all the three, i.e. the current
I, radius R and number of turns N are doubled, then, the magnetic field at its centre becomes:
(a) Double
(b) Half
(c) Four times
(d) One fourth
उत्तर
Double
`B = (mu_0NI)/R`
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संबंधित प्रश्न
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