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प्रश्न
Current in a circuit falls from 5.0 A to 0.0 A in 0.1 s. If an average emf of 200 V induced, give an estimate of the self-inductance of the circuit.
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उत्तर
Initial current, I1 = 5.0 A
Final current, I2 = 0.0 A
Change in current, dI = I1 − I2 = 5 A
Time taken for the change, t = 0.1 s
Average emf, e = 200 V
For self-inductance (L) of the coil, we have the relation for average emf as:
e = `"L""dl"/"dt"`
`"L" = "e"/((("dl")/("dt")))`
= `200/(5/0.1)`
= 4 H
Hence, the self-induction of the coil is 4 H.
संबंधित प्रश्न
Two solenoids have identical geometrical construction but one is made of thick wire and the other of thin wire. Which of the following quantities are different for the two solenoids?
(a) self-inductance
(b) rate of Joule heating if the same current goes through them
(c) magnetic field energy if the same current goes through them
(d) time constant if one solenoid is connected to one battery and the other is connected to another battery.
Explain why the inductance of two coils connected in parallel is less than the inductance of either coil.
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What is the unit of self-inductance of a coil?
A coil of wire of a certain radius has 600 turns and a self-inductance is 108 mH. The self-inductance of a second similar coil of 500 turns will be:
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An air-cored solenoid, 40 cm long and of cross-sectional area 5 cm2, is tightly wound with 400 turns of copper wire and carries a steady current of 10 A. (a) Calculate the self-inductance of the solenoid. (b) Find the emf induced if the current in the solenoid decreases to zero in 0.2 s.
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Equivalently, self-inductance equals the magnitude of the induced EMF per unit what?
What does \[\varepsilon\] represent, and what is its SI unit?
For a long solenoid of length \[l\] with \[N\] total turns, what is the number of turns per unit length?
Which set of quantities describes the long solenoid used to derive its self-inductance?
What is the magnetic flux through one turn of the long solenoid?
What is the self-inductance of a long air-core solenoid?
Using \[B=\mu_0nI\], what is the magnetic energy density inside the air-core solenoid?
What is the SI unit of both self-inductance and mutual inductance?
