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The peak factor of the sinusoidal wave form is?

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Important Questions on Alternating Current

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Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

The instantaneous voltages at three terminals marked

X, Y

and

Z

are given by

V_{X} = V_{0} \sin ω t

V_{Y} = V_{0} \sin (ω t + \frac{2 π}{3})

and

V_{Z} = V_{0} \sin (ω t + \frac{4 π}{3}) .

An ideal voltmeter is configured to read rms value of the potential difference between its terminals. It is connected between points

X

and

Y

and then between

Y

and

Z

. The reading(s) of the voltmeter will be

EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

An alternating current is given by the equation

i = i_{1} \sin ω t + i_{2} \cos ω t

. The rms current will be:

EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

A C

source rated

220 V, 50 Hz

is connected to a resistor. The time taken by the current to change from its maximum to the rms value is :

EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

The mean or average value of AC over a complete cycle is

EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

In the circuit shown below, if $V_{s} = V_{m} \sin ω t$ and the diode is ideal, the average value of voltage across $R_{L}$ is (Assume source resistance is zero)

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MEDIUM

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

40 μF

capacitor is connected to a

200 V

50 Hz

AC supply. The rms value of the current in the circuit is, nearly:

EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

A C

current is given by

I = I_{1} s i n ω t + I_{2} c o s ω t .

A hot wire ammeter will give a reading:

EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

The rms value of potential difference $V_{0}$ shown in figure is

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EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

The RMS value of emf given by

E = (8 \sin ω t + 6 \cos ω t)

volt is

EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

In the given circuit the peak voltages across $C, L$ and $R$ are $30 V, 110 V$ and $60 V$ respectively. The rms value of the applied voltage is

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EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

The frequency of an alternating current is

50 Hz

. What is the minimum time taken by current to reach its peak value from zero value?

EASY

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

In Karnataka, the normal domestic power supply AC is

220 V, 50 H z .

Here,

220 V

and

50 H z

refer to

HARD

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

An alternating current is given by

I = I_{1} cos ω t + I_{2} sin ω t

. The root mean square current is given by,

MEDIUM

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

Find the rms value of the saw tooth wave form shown in figure -

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HARD

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

For An alternating current :

HARD

Physics>Electricity and Magnetism>Alternating Current>Average and RMS Value of Alternating Current and Voltage

An ac circuit of angular frequency

ω

is fed across a resistor

R

and a capacitor

C

in series. The current registered is

I

. If now, the frequency of the source is changed to

\frac{ω}{3}

but maintaining the same voltage, the current in the circuit is found to be halved. Calculate the ratio of reactance to resistance at the original frequency