Electromagnetic...

Complete the following statement. For electromagnetic induction to occur:

A helicopter rises vertically with a speed of 100 m/s. If helicopter has length 10 m and horizontal component of earth's magnetic field is $$5\times 10^{-3} Wb/m^2$$, then the induced emf between the tip of nose and tail of helicopter is:

If circular coil with $$N_{1}$$ turns is changed in to a coil of $$N_{2}$$ turns. What will be the ratio of self inductances in both cases.

 If coil is placed perpendicular to field lines then number of lines passing through coil are :

 Alternative current generator is basically based upon :

Flux density under trailing pole tips in case of generator will :

Alternating current is flowing in inductance L and resistance R. The frequency of source is $$\displaystyle\frac{\omega}{2\pi}$$. Which of the following statement is correct.

In a transformer, coefficient of mutual inductance between primary and secondary coil is 0.2 H. When current changes by 5 Na in the primary, then: the induced era in the secondary will be 

The dimensions of self-inductance L are :

A coil carrying electric current is placed in uniform magnetic field, then :