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प्रश्न
A conducting rod held horizontally along East- West direction is dropped from rest from a certain height near the Earth’s surface. Why should there be an induced emf across the end of the rod? Draw a plot showing the instantaneous variation of emf as a function of time from the instant it begins to fall.
उत्तर
Emf induced due to change of magnetic flux across rod due to the presence of Earth’s magnetic field.
We know,
`E =(dphi_B)/(dt)`
As the Earth’s magnetic field is uniform,
`E =-Blv = -Bl (dx)/(dt)`
Hence,
संबंधित प्रश्न
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