Coil Rotating in Uniform Magnetic Induction

In an ac generator, a rectangular coil of $100$turns each having area $14\times {10}^{-2} {\mathrm{m}}^2$ is rotated at $360 \mathrm{rev} {\min }^{-1}$about an axis perpendicular to a uniform magnetic field of magnitude$3.0 \mathrm{T}$ . The maximum value of the emf produced will be ______ $\mathrm{V}$ . [Take $\pi =\frac{22}{7}$ ]

In which positions of the coil the magnitude of induced emf in the coil of AC is (a) maximum and (b) minimum

An a.c. generator having a constant magnetic field is conneted to a resistive load. What will be the effect of doulbling the speed of rotation on:

(i) frequency of a.c.

(ii) generated e.m.f.

(iii) mechanical power required to rotate the generator ?

A $220 \mathrm{V}$ dc machine has an armature resistance of $1\mathrm{\Omega }$. If the full load current is $20 \mathrm{A}$, the difference in the induced voltages when the machine is running as a motor, and as a generator is

A $220 \mathrm{V}$ dc machine has an armature resistance of $1\mathrm{\Omega }$. If the full load current is $20 \mathrm{A}$, the difference in the induced voltages when the machine is running as a motor, and as a generator is

How the direction of current changes in the armature coil of AC generators?

Deduce the expression for peak induced emf generated from an AC generator.

The frequency of a.c. supply in India is _____.

If an a.c. generator consists of a coil of $1000$ turns, each of area $100 {\mathrm{cm}}^2$ rotating in a uniform magnetic field of $3.6\times {10}^{-2}\mathrm{T}$. If the average value of induced emf is $2.67 \mathrm{V}$, calculate the frequency of the rotation of the coil.

What is the principle of an a.c generator? What determines the frequence of the induces emf.

The frequency of an a.c. generator depends upon:

1. What is the average value of the shaded portion of the graph of $\mathrm{E} \mathrm{vs} \mathrm{T}$.What will be the reading of a.c voltmeter?

A circular coil having $20$ turns, each of radius $8 \mathrm{cm}.$ is rotating about its vertical diameter with an angular speed of $50 \mathrm{rads}/\sec$ in a uniform horizontal magnetic field of $30 \mathrm{mT}$. Obtain maximum, average and r.m.s.value of emf induced in the coil. If the coil forms a close loop of resistance $10\Omega$, how much power is dissipated as heat?

When the sine of angle in an electric generator is $0°$, the induced emf is :

If frequency of an AC generator is doubled, the maximum value of emf induced in its coil will:

A coil of $500$ turns and area $100 {\mathrm{cm}}^2$ is placed at right angles to a magnetic field of $5\times {10}^{-2} \mathrm{Wb}/{\mathrm{m}}^2$. If the speed of rotation is $300 \mathrm{rps}$, what is the maximum value of induced e.m.f. in the coil?

At which position of the plane of the rotating coil with the direction of magnetic field, the e.m.f. induced in the coil is maximum?

In most AC generators, the coils are held stationary and magnetic field is rotated.

A square coil of $20$ turns has sides of length $10 \mathrm{cm}$. The flux density in which the coil rotates is $10 \mathrm{Wb}/{\mathrm{m}}^2$. What is the angular velocity of the coil if the maximum e.m.f. produced is $200 \mathrm{V}$?

A coil of $200$ turns and area $200 {\mathrm{cm}}^2$ is placed at right angles to a magnetic field of $3\times {10}^{-2} \mathrm{Wb}/{\mathrm{m}}^2$. If the speed of rotation is $400 \mathrm{rps}$, what is the maximum value of induced e.m.f. in the coil?