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प्रश्न
What are the values of the self-induced emf in the circuit of the previous problem at the times indicated therein?
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उत्तर
Given:-
Self-inductance, L = 1 H
For an inductor of self-inductance L, the emf induced is given by
`e = L(di)/(dt)`
(a) At t = 100 ms,
`(di)/(dt)=0.27"A/s"`
∴ Induced emf, `e = L(di)/(dt)=1xx0.27=0.27 V`
(b) At t = 200 ms,
`(di)/(dt)=0.036"A/s"`
∴ Induced emf `= L(di)/(dt)=1xx0.036=0.036V`
(c) At t = 1 s,
`(di)/(dt)=4.1xx10^-9"A/s"`
∴ Induced emf `=L(di)/(dt)=4.1xx10^-9V`
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संबंधित प्रश्न
Define self inductance. Write its S.I. units.
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.
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Obtain an expression for the self-inductance of a solenoid.
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Calculate the self-inductance of a coil using the following data obtained when an AC source of frequency `(200/pi)` Hz and a DC source are applied across the coil.
| AC Source | ||
| S.No. | V (volts) | I (A) |
| 1 | 3.0 | 0.5 |
| 2 | 6.0 | 1.0 |
| 3 | 9.0 | 1.5 |
| DC Source | ||
| S.No. | V (volts) | I (A) |
| 1 | 4.0 | 1.0 |
| 2 | 6.0 | 1.5 |
| 3 | 8.0 | 2.0 |
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