Advertisements
Advertisements
Question
What are the values of the self-induced emf in the circuit of the previous problem at the times indicated therein?
Advertisements
Solution
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`
APPEARS IN
RELATED QUESTIONS
Consider the self-inductance per unit length of a solenoid at its centre and that near its ends. Which of the two is greater?
A coil of self-inductance 3 H carries a steady current of 2 A. What is the energy stored in the magnetic field of the coil?
Consider a solenoid carrying supplied by a source with a constant emf containing iron core inside it. When the core is pulled out of the solenoid, the change in current will ______.
An e.m.f. of 10 volt is produced by a self inductance when the current changes at a steady rate from 6 A to 4 A in 1 millisecond. The value of self inductance is ____________.
Magnetic flux of 12 microweber is linked with a coil. When current of 3 mA flows through it, the self inductance of the coil is ____________.
A resistance of 100 `Omega`, inductor of self-inductance`(4/pi^2)` H and a capacitor of unknown capacitance are connected in series to an a.c. source of 200 V and 50 Hz. When the current and voltage are in phase, the capacitance and power dissipated is respectively ____________.
A coil is wound on a frame of rectangular cross-section. If all the linear dimensions of the frame are increased by a factor 2 and the number of turns per unit length of the coil remains the same, self-inductance of the coil increases by a factor of ______.
An inductor may store energy in
The self-inductance depends upon ______.
The self inductance L of a solenoid of length l and area of cross-section A, with a fixed number of turns N increases as ______.
In a fluorescent lamp choke (a small transformer) 100 V of reverse voltage is produced when the choke current changes uniformly from 0.25 A to 0 in a duration of 0.025 ms. The self-inductance of the choke (in mH) is estimated to be ______.
State the factors on which the magnetic coupling coefficient of two coils depends.
What is meant by magnetic coupling coefficient?
Two inductor coils with inductance 5 mH and 15 mH are connected in parallel. The resultant inductance of the combination of the two coils is ______.
The current flowing through an inductor of self inductance ‘L’ is continuously increasing at constant rate. The variation of induced e.m.f. (e) versus `((dI)/(dt))`is shown graphically by:
What property of a coil is called self-inductance?
What does \[L\] represent?
What does \[I\] represent, and what is its SI unit?
What is the magnetic field inside a long air-core solenoid?
Which applications are associated with self-inductance and mutual inductance, respectively?




