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प्रश्न
In what respect is a toroid different from a solenoid?
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उत्तर
Toroid
• It is a hollow circular ring on which a large number of turns of a wire are closely wound.
• Three Amperian loops (1, 2, and 3) are shown by dotted lines.
• Magnetic field along loop 1 is zero because the loop encloses no current.
• Magnetic field along loop 3 is zero because the current coming out of the paper is cancelled exactly by the current going out of it.
• Magnetic field at S (along loop 2):
From Ampere’s law,
∴B (2πr) = μ0NI
Where,
B → Magnetic field
r → Radius
I → Current
N → Number of turns of toroidal coil
`therefore B=(mu_0NI)/(2pir)`
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संबंधित प्रश्न
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The length of a solenoid is 0.4 m and the number turns in it is 500. A current of 3 amp, is flowing in it. In a small coil of radius 0.01 m and number of turns 10, a current of 0.4 amp. is flowing. The torque necessary to keep the axis of this coil perpendicular to the axis of solenoid will be ______.
