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

Main reasons for worldwide use of A. C is

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

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

Capacitive reactance Xc =

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

The sum of positive and negative peak values is called:

As a result of modulation, the resulting wave is called

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

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

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

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

Which of the following electromagnetic waves have shortest wavelength?

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

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

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

The speed of electromagnetic wave in vacuum is given by

At high frequency the value of reactance of capacitor will he

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

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

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

The sum of positive and negative peak value is called

Electromagnetic waves are, generated when

In RLC parallel circuit the resonance frequency is

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

Average value of current and voltage over a complete cycle is

The power factor in wattles current is

The range of values of power factor is

In a pure inductive A.C. circuit the current

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

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

Power factor is equal to:

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

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

Direct current cannot flow through:

The reactance Of capacitor is equal to

Power dissipated in pure inductor is:

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

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

Waves we prefer for transmission of radio signals have

Electromagnetic waves transport

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

The range or F.M transmission frequencies is from

The frequency range. for F.M is given by

Modulation can be achieved by

AN inductor may store energy in:

The flow of D.C. current is opposed by

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

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

Choke used to limit high frequency A.C has

The power factor of RL-series circuit is :

The amplitude modulated transmission waves have frequencies range:

In R-L series circuit phase angle is given by

The power factor of an A.C circuit has.

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

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

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

Impedance Z can he expressed as;

The phase angle at +vc (positive) peak is

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

Dimensions of RC matches with

The most common source of A.C is:

Direct current cannot flow through

Which one is not present in AC generator?

In case of capacitor, the unit of reactance is:

AC can be converted into DC by:

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

In the modulation process, low, frequency signal is called

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

High frequency radio wave is called as:-.

The reactance of an inductor is

Choke consumes extremely small:

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

Choke coil in A.C circuit is used for

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

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

Electromagnetic waves emitted from radio antenna are:

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

In alternating current, Inductors behave like

In pure RLC circuit, the energy is dissipated in:

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

A.C. through inductor, the applied voltage:

During each cycle AC voltage reaches a peak value

The combined effect of resistance and reactance is known as:

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

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

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

The waveform of alternating voltage is a:

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

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

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

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

AC voltmeter measure

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

In the modulation process, high frequency signal is called

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

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

The wire receiving the waves is known as

The frequency of AC in Pakistan is;

Electromagnetic waves do not transport any: