Sage-Tips

When the coils are connected in series with the windings in opposite directions is the total inductance greater or lesser than twice the self inductance of a single coil Why?

One important point to remember about inductors in series circuits, the total inductance ( LT ) of any two or more inductors connected together in series will always be GREATER than the value of the largest inductor in the series chain.

What is effective self inductance?

Self inductance is an effect that is noticed when a single coil experiences the effect of inductance. Under the effects of self inductance and changes in current induce an EMF or electro-motive force in that same wire or coil, producing what is often termed a back-EMF.

Under what condition mutual inductance between two coils is equal to the self inductance?

EMF in the secondary coil generates only when there is a change in the current I1. ∴The coefficient of mutual inductance of two coils is equal to the induced emf in the S coil when the rate of change of current in the P coil is unity.

When inductors are connected in series in a circuit the total inductance is?

When inductors are connected in series, the total inductance is the sum of the individual inductors’ inductances. To understand why this is so, consider the following: the definitive measure of inductance is the amount of voltage dropped across an inductor for a given rate of current change through it.

When two coils are wound on each other the mutual induction between the coil is maximum?

mutual inductance
When the two coils are wound on each other, the coefficient of coupling is maximum and hence mutual inductance between the coil is maximum.

When two coils are magnetically isolated then coefficient of coupling k is?

k=1, when the flux produced by one coil, completely links with the other coil and is called magnetically tightly coupled. k=0, when the flux produced by one coil, does not link at all with the other coil and thus the coils are said to be magnetically isolated.

What is self inductance of a coil?

Self-inductance of a coil is defined as the phenomenon due to which an emf is induced in a coil when the magnetic flux of coil , linked with the coil changes or current in coil changes . Its S.I. unit is Henry(H) .

When two inductors L1 and L2 are connected in series the equivalent inductance is?

Two inductances L1 and L2 are connected in series and are separated by a large distance: (i) Show that their equivalent inductance is L1+L2.

What do you understand by mutual induction on what factors the mutual inductance between two coils depend?

Note: Mutual inductance between two coils depends on permeability of core, the number of their turns and cross sectional area of the common core. Mutual inductance of the coils also depends on their separation as well as their relative orientation.

When two coils connected in series aiding what is the equivalent inductance?

The inductance of series connected inductors is calculated as the sum of the individual inductances of each coil since the current change through each coil is same. V = L di/ dt. This means the total inductance of the series connection is the sum of individual inductances of all inductors.

How do you find mutual inductance between two coils?

The mutual inductance M21 of coil 2 with respect to coil 1 is the ratio of the flux through the N2 turns of coil 2 produced by the magnetic field of the current in coil 1, divided by that current, that is, M21=N2Φ21I1. M12=N1Φ12I2. M=N2Φ21I1=N1Φ12I2.

What happens to the coupling coefficient when the flux linkage of coil 1 and coil 2 increases?

When the flux linkage of coil 1 and coil 2 increases, its mutual inductance increases. The coupling coefficient is directly proportional to the mutual inductance hence as mutual inductance increases, the coupling coefficient increases.

How do you calculate the effective inductance of a magnetic coil?

The coils can be connected in series in such a way that the currents through them can produce individual magnetic flux either aiding or opposing one another. So the effective inductance, L can be either L1+L2+2M or L1+L2–2M respectively. M is the mutual inductance and M = k (L1L2)^0.5, where k = coefficient of coupling (<1).

What affects the mutual inductance of a series connected of inductors?

This mutual inductance may increase or decrease the total inductance of the series circuit. The factor that affects the mutual inductance of a series connected of inductors is the distance between the coils and their orientation. The mutually connected inductors can coupled in two types

What happens when you connect two coils in series opposition?

Answer to this is that , depending upon the connection you made by this coil . If you connect in series opposition then you need to subtract. *series opposition is a series connection in which magnetic field of both coil gets oppose to eachother . As shown in the above figure, there are two ways of connecting the coils in series they are

What is the co-efficient of coupling of two coils?

Two coils have self-inductances of 10 H and 2 H, the mutual inductance being zero. If the two coils are connected in series, the total inductance will be 27. In case all the flux from the current in coil 1 links with coil 2, the co-efficient of coupling will be 28. A coil with negligible resistance has 50V across it with 10 mA.