Electromagnetic...

The SI unit of inductance, the henry, can be written as :

Two coils of self inductances $$6mH$$ and $$8mH$$ are connected in series and are adjusted for highest co-efficient of coupling. Equivalent self inductance $$L$$ for the assembly is approximately

An aircraft with a wingspan of $$40\ m$$ flies with a speed of $$1080\ km/hr$$ in the eastward direction at a constant altitude in the northern hemisphere, where the vertical component of the earth's magnetic field $$1.75\times 10^{-5}T$$. Then the emf developed between the tips of the wings is

While keeping area of cross-section of a solenoid same, the number of turns and length of solenoid one both doubled. The self inductance of the coil will be

The self inductance of a coil having 500 turns is 50 mH. The magnetic flux through the cross-sectional area of the coil while current through it is 8 mA is found to be

A solenoid $$30 cm$$ long is made by winding $$2000$$ loops of wire on an iron rod whose cross-section is $$1.5{ cm }^{ 2 }$$. If the relative permeability of the iron is $$6000$$, what is the self-inductance of the solenoid?

In figure when key is pressed the ammeter A reads i ampere. The charge passing in the galvanometer circuit of total resistance R is Q. The mutual inductance of the two coils is :

A metal disc of radius R rotates with an angular velocity, $$\omega = 1   rad/s$$  about an axis perpendicular to its plane passing through its centre in a magnetic field of induction B acting perpendicular to the plane of the disc. The induced e.m.f. between the rim and axis of the disc is:

If emf induced in a coil is $$2V$$ by changing the current in it from $$8A$$ to $$6A$$ in $$2\times {10}^{-3}s$$, then the coefficient of self induction is

Direction of induced EMF can be found from