PHYSICS 2nd Year MCQs Chapter No.5 ALTERNATING CURRENT Online MDCAT & ECAT Preparation Test No.1

Choke coil in A.C circuit is used for

The flow of D.C. current is opposed by

The reactance of an inductor is

The process of combining the low frequency signal with a high frequency signal is called

The frequency of AC in Pakistan is;

In alternating current, Inductors behave like

The amplitude modulated transmission waves have frequencies range:

Electromagnetic waves do not transport any:

The highest value reached by the Voltage or current in one cycle is called;

A.C. through inductor, the applied voltage:

In R-L-C Circuit, the energy is dissipated in:

The phase angle between the voltage and current through resistor is:

Average value of current and voltage over a complete cycle is

In the modulation process, high frequency signal is called

The opposition offered by a capacitor.to the flow of an A. C is called

The reactance of a capacitor at 50Hz is 10 Ohm Which of the following will be its reactance at 100 Hz?

In a pure inductive A.C. circuit the current

At high frequency the value of reactance of capacitor will he

The frequency of electromagnetic waves received through a LC - circuit is adjusted by

The piece of wire through which charges are made to accelerate by mean o me waves is known as

The basic circuit element in a D.0 circuit which controls the current and voltage is

In three phase AC generator the phase difference between each pair of coil is:

The amplitude modulation (A.M.) transmission, frequencies range from

In an electromagnetic waves, the electric and magnetic field are:

For frequency modulated signal, the frequency of the modulated carrier wave is highest when the signal amplitude is at its

High frequency radio wave is called as:-.

The sharpness of resonance RLC series resonant circuit, as the resistance of the circuit is increased,

The range of values of power factor is

The power factor of an A.C circuit has.

In case of capacitor, the unit of reactance is:

Which one is not present in AC generator?

The mean value of A.C. in a cycle is :

The frequency range. for F.M is given by

As a result of modulation, the resulting wave is called

The frequency of A.C. source used in Pakistan is;

The frequency of the range 20 to.20,000 Iii is:

Direct current cannot flow through:

Direct current cannot flow through

Power factor is equal to:

When we accelerate the charges, which type of waves are produced.

If E and B be electric and magnetic field vectors of an electromagnetic wave, Then propagation of wave then propagation of wave is along the direction of

Modulation can be achieved by

Phase difference between V and I of an A. C through resistor is

Capacitive reactance Xc =

The peak value of A.C is 2?2 A Which of the following will be its apparent value?

Choke consumes extremely small:

In RLC series circuit at resonance the phase difference between capacitor and inductor reactance's is:

The slope of q-t curve at any instant of time gives:

When electrons in a transmitting antenna vibrate 94000 times each having frequency:

In tuning circuit if capacitance is doubled and inductance is halved then its frequency

The velocity of an oscillating charge as it moves to and fro along the wire is

The most common source of A.C is:

During each cycle AC voltage reaches a peak value

For frequency modulated signal, the frequency of the modulated carrier wave is at its normal value when the signal amplitude is at its

Impedance Z can he expressed as;

At resonance frequency, the impedance of RLC - Parallel Circuit is

The wire receiving the waves is known as

In Pakistan, the frequency of A.C. supply is :

Electromagnetic waves emitted from radio antenna are:

The phase difference between current and voltage in an Inductive circuit is

Power dissipated in pure inductor is:

In our radio receiver set, when we change station, or change the frequency we actually adjust the :due of

The speed of electromagnetic wave in vacuum is given by

In R-L series circuit phase angle is given by

Which of the following electromagnetic waves have shortest wavelength?

The peak value of A.C source is 20 A, then its rrms value will be:

AC can be converted into DC by:

Dimensions of RC matches with

The impedance. Of RLC series circuit at, resonance is equal to;

In RLC parallel circuit the resonance frequency is

AN inductor may store energy in:

Electromagnetic waves transport

Main reasons for worldwide use of A. C is

The sum of positive and negative peak value is called

In RIC series circuit Xl=Xc Which of the following will be the power factor?

AC voltmeter measure

The effective value of A.C in a circuit is 10A Which of the following will be its peak value.

The combined effect of resistance and reactance is known as:

The waveform of alternating voltage is a:

The sum of positive and negative peak values is called:

The power factor of RL-series circuit is :

Which of the following radiations forms the part of electromagnetic spectrum?

In pure RLC circuit, the energy is dissipated in:

For frequency modulated signal, the frequency of the modulated carrier wave is lowest when the signal amplitude is at its

The range or F.M transmission frequencies is from

An electric bulb is designed to operate at 12V DC. It is connected to AC and gives same brightness then peak AC value of voltage is

At resonance frequency, the impedance of RLC series circuit is:

Which of the following is the time taken by an A.C of frequency 50 Hz to complete one cycle?

100 μf capacitor is connected to an AC-voltage of 24 V and frequency of 50 Hz. The reactance of the capacitor is

Waves we prefer for transmission of radio signals have

The velocity of an oscillating charge as it moves to and fro along a wire is:

The phase angle at +vc (positive) peak is

In three phase A.C supply coils are inclined at an angle of

The power factor in wattles current is

The frequency modulation (F.M.) transmission, frequencies range from

Electromagnetic waves are, generated when

Choke used to limit high frequency A.C has

In the modulation process, low, frequency signal is called

The reactance Of capacitor is equal to