Advertisements
Advertisements
प्रश्न
Explain the phenomenon of mutual induction.
Advertisements
उत्तर
a. The phenomenon of production of induced e.m.f in one coil due to change of current in the neighbouring coil is called mutual induction. The e.m.f so induced is called mutually induced e.m.f.
b.
Consider primary coil P and secondary coil S fitted with galvanometer G and placed very close to each other as shown in figure. The coil P is connected in series with the source of e.m.f (battery) and key K.
c. When tap key K is pressed, current IP passes through the coil P. Magnetic flux φS linked with secondary coil S at any instant is directly proportional to current IP through primary coil P at that instant.
∴ φS ∝ IP
∴ φS = M IP ….(i)
where M is constant called coefficient of mutual induction or mutual inductance of the coil.
d. e.m.f induced in S at any instant is given by,
`e_S = -(dphi_s)/(dt)`
`e_S=-d/(dt)(MI_P)` [From equation (i)]
∴ ` e_S = − M (dI_P)/dt`
∴ Magnitude of induced e.m.f is given by,
`|e_S|=|-(MdI_P)/dt|`
`e_s=(MdI_P)/dt`
`M=e_S/((dI_P)/dt)`
APPEARS IN
संबंधित प्रश्न
The co-efficient of mutual induction between primary and secondary coil is 2H. Calculate induced e.m.f. if current of 4A is cut off in 2.5 x 10-4 seconds
If the radius of a sphere is doubled without changing the charge on it, then electric flux originating from the sphere is ______.
In an experiment, two coils c1 and c2 are placed close to each other. Find out the expression for the emf induced in the coil c1 due to a change in the current through the coil c2.
The current flowing through an inductor of self inductance L is continuously increasing. Plot a graph showing the variation of Magnetic potential energy stored versus the current.
A long solenoid with 15 turns per cm has a small loop of area 2.0 cm2 placed inside the solenoid normal to its axis. If the current carried by the solenoid changes steadily from 2.0 A to 4.0 A in 0.1 s, what is the induced emf in the loop while the current is changing?
Explain self induction and mutual induction
Define coefficient of mutual induction.
Consider two concentric circular coils, one of radius r1 and the other of radius r2 (r1 < r2) placed coaxially with centers coinciding with each other. Obtain the expression for the mutual inductance of the arrangement.
A coil of self-inductance 2.5H and resistance 20Ω is connected to a battery of emf 120V having the internal resistance of 5 n. Find:
1) The time constant of the circuit.
2) The current in the circuit in steady state
Two circular loops are placed with their centres separated by a fixed distance. How would you orient the loops to have (a) the largest mutual inductance (b) the smallest mutual inductance?
A solenoid of length 20 cm, area of cross-section 4.0 cm2 and having 4000 turns is placed inside another solenoid of 2000 turns having a cross-sectional area 8.0 cm2 and length 10 cm. Find the mutual inductance between the solenoids.
A pair of adjacent coils has a mutual inductance of 1.5 H. If the current in one coil changes from 0 to 10 A in 0.2 s, what is the change of flux linkage with the other coil?
An emf of 96.0 mV is induced in the windings of a coil when the current in a nearby coil is increasing at the rate of 1.20 A/s. What is the mutual inductance (M) of the two coils?
The mutual inductance of two coils is 10 mH. If the current in one of the coil changes from 5 A to 1 A in 0.2 s, calculate the emf induced in the other coil. Also calculate the induced charge flowing through the coil if its resistance is 5 Ω.
Define mutual inductance.
The dimensions of self or mutual inductance are given as ______.
In an induction coil, the coefficient of mutual inductance is 6 henry. If a current of 10 ampere in the primary coil is cut-off in `1/1500"s"`, the e.m.f. at the terminals of the secondary coil will be ____________.
An alternating current of frequency 200 rad/s and peak value 1 A is applied to the primary of a transformer. If the coefficient of mutual induction between the primary and the secondary is 1.5H, then the voltage induced in the secondary will be approximately (π = 2217)
Two different wire loops are concentric and lie in the same plane. The current in the outer loop (I) is clockwise and increases with time. The induced current in the inner loop.
The mutual inductance between two coplanar concentric rings A and B of radii 'R1' and 'R2' placed in air when a current 'I' flows through ring A is (R1 >> R2) (µ0 = permeability of free space) ____________.
The mutual inductance between two coils is 0.09 henry. If the current in the primary coil changes from 0 to 20 A in 0.006 s, the e.m.f. induced in the secondary coil at that instant is ____________.
The mutual inductance of a pair of coils is 0.75 H. If current in the primary coil changes from 0.5 A to zero in 0.01 s, find average induced e.m.f. in secondary coil ______.
If number of turns in primary and secondary coils is increased to two times each, the mutual inductance ______.
The mutual inductance M12 of coil 1 with respect to coil 2 ______.
- increases when they are brought nearer.
- depends on the current passing through the coils.
- increases when one of them is rotated about an axis.
- is the same as M21 of coil 2 with respect to coil 1.
There are two coils A and B seperated by some distance. If a current of 2A flows through A, a magnetic flux of 10-2 Wb passes through B (no current through B). If no current passes through A and a current of 1A passes through B, what is the flux through A?
A toroid is a long coil of wire wound over a circular core. The major radius and cross-sectional radius of the toroid are R and r, respectively. The coefficient of mutual induction of the toroid is ______.
(The magnetic field in it is uniform, N = number of turns, R >> r, μ0 = permeability of free space)
The mutual inductance of a pair of adjacent coils is 1.5 H. If the current is one coil changes from 5 A to 10 A in 0.1 s, the rate of change of magnet flux linkage is ______.
State and define the SI unit of mutual inductance.
Two coils having self inductances L1 = 75 mH and L2 = 55 mH are coupled with each other. The coefficient of coupling (K) is 0. 75. Calculate the mutual inductance (M) of the two coils
The coefficient of mutual induction is 2 H and induced e.m.f. across secondary is 2 kV. Current in the primary is reduced from 6 A to 3 A. The time required for the change of current is ______.
The mutual inductance between a primary and secondary circuit is 0.4 H and the resistance in these circuits are \[20\Omega\] and \[4\Omega\] respectively. To produce a current of 0.5 A in the secondary, current in the primary must be changed at the rate of ______.
Which property of two coils describes a change in current in one coil inducing an emf in the other?
Which relation defines mutual inductance using the flux linkage \[N_2\phi_{21}\] and current \[I_1\] ?
What do \[L_1\] and \[L_2\] represent in \[M=K\sqrt{L_1L_2}\] ?
Which range and unit description apply to the coefficient of coupling \[K\] ?
Which dimensional formula applies to mutual inductance?
Which pair gives other units of mutual inductance?
The Henry, the SI unit of mutual inductance, is named after whom?
Which equivalence correctly states the value of \[1\ \mathrm{H}\] ?
What does the Reciprocity Theorem of Mutual Inductance state?
How does increasing the number of turns \[N_1\] and \[N_2\] affect mutual inductance?
What happens to mutual inductance as the distance between coils increases?
What does the coupling factor \[K\] quantify?
What is the total flux linkage of secondary solenoid \[S_2\] ?
What is \[M_{21}\] for two coaxial solenoids with the smaller solenoid inside the larger?
Why can \[B_2\] be assumed uniform across the entire area of the inner coil?
What is the magnetic flux through the inner small coil when current \[I_2\] flows in the outer large coil?
What is the mutual inductance of a small circular coil of radius \[r_1\] at the centre of a large circular coil of radius \[r_2\] when \[r_1\ll r_2\] ?
How does a transformer use mutual inductance?
