Question

The electric main in a house is marked 220V-50Hz. Write down the equation for instantaneous voltage.

Solution

Correct option is

The equation for the alternating voltage is 

Where V is instantaneous voltage and Vo the peak value of the voltage.  

.   

Also = 50 Hz. Substituting values of Vo and f in eq. (i), we get 

       

SIMILAR QUESTIONS

Q1

The induced emf in armature will be zero, when armature is rotated at an angle

Q2

An a.c. source is of 120 volt , 60Hz the value of the voltage after 1/360  sec from the start will be

Q3

Resonance  frequency of a circuit is f if the capacitance is made 4 times the initial value , then the resonance frequency will become

Q4

In and A.C. circuit , minimum voltage of 423 Volt. Its effective voltage is

Q5

The  average power  dissipation in a pure capacitor in A.C. circuit is

Q6

A 100-turn rectangular coil of size 0.20 m × 0.10 m rotates in a magnetic field of 0.003 Wb m–2 with a frequency of 1200 rpm about an axis normal to the field. Find the maximum value of the induced emf

Q7

An a.c. generator consisting of a coil of 100 turns and cross-sectional area of 3 m2 is rotating at a constant angular speed of 60 rad s–1 in a uniform magnetic field of 0.04 T. The resistance of the coil is 500 . Calculate maximum current drawn from the generator, and power dissipation in the coil. From where does the power come? 

Q8

An a.c. generator consists of a coil of 50 turns and area 2.5 m2 rotating at an angular speed of 60 rad s–1 in a uniform magnetic field of 0.30 T. The resistance of the circuit including that of the coil is 500 . Find the maximum current drawn from the generator.    

Q9

In a dynamo, a coil of area 0.2 m2 and having 100 turns rotates in a magnetic field of 0.1 Wb m–2 with an angular velocity of 100 rad s–1. The output terminals are connected through a resistance of . Calculate the torque , as a function of time t, required to keep the coil rotating.

Q10

A sinusoidal voltage V = 200 sin 314t is applied to a  resistor. Find the frequency of the supply.