(a) State the principle of an ac generator and explain its working with the help of a labelled digram. Obtain the expression for the emf induced in a coil having N turns each of cross-section area.
A, rotating with a constant angular speed `omega` in a magnetic filed `omega`, directed prependicular to the axis of rotation.
(b) An aeroplane if flying horizontally for west to east with a velocity of 900 km/hours. Calcuate the potential difference developed between the ends of its wings having a span of 20n. The horizontal component of the Earth's magnetic field is `5 xx 10^(-4) T` and the angle of dip is `30^(@)`.