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Electric Charges and Fields

Electrostatic Potential and Capacitance

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Magnetism and Matter

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Experimental Skills in Physics

If an antenna radiates electromagnetic wave from a height of h the range of coverage d is given by where R is radius of earth

asked Mar 17, 2014 by sreemathi.v

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Which of the following statements are correct?

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In amplitude modulation

asked Mar 17, 2014 by sreemathi.v

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Attenuation is

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Surface wave propagation is done near the surface of earth.Surface wave propagation is sutable upto

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Optical fibres use for transmission the principle of

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For commercial FM transmission maximum frequency deviation allowed

asked Mar 17, 2014 by sreemathi.v

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What is the modulating index of an FM carrier having carrier signal swing of 60KHz and modulating signal frequency of 2KHz

asked Mar 17, 2014 by sreemathi.v

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What is the modulating factor given maximum peak to peak voltage of an AM is 10mv and minimum peak to peak voltage is 2mv.

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A 1KHz modulating voltage is supplied to a FM(frequency modulator) produces a frquency deviation of 1.2KHz.The modulating index is

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Amplitude of carrier wave is 20v amplitude of signal is 2v.Percentage of modulation is

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What type of data does optical fibres carry

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When microwave signals propagate along the curvature of the earth,the effect is called

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An FM signal has deviation 75KHz and the highest frequency of modulation is 15KHz.Band width is

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An oscillator is producing a FM wave of frequency 1KHz with a variation of 5KHz.What is modulating index.

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An FM signal has a frequency of 105MHz and highest frequency acquired is 105.05MHz when modulated by a signal.The carrier swing is

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Power of carrier wave is 1000Watt.What is the required power of the signal to modulate it 100%

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An amplitude modulated wave has 800watt of total power content.For 100% modulation the carrier should have power content equal to

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If level of modulation is increased ________ power is increased

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An audio signal given by $20\sin(2\pi \times 4000t)$ is used for modulating carrier wave given by $40\sin (2\pi\times 400000t)$ .The frequency spectrum of modulated wave

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An audio signal $20\sin(2\pi\times 400t)$ is used to modulating a carrier wave given by $40\sin(2\pi\times 40000t)$ .The percentage modulation is

asked Mar 17, 2014 by sreemathi.v

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In AM transmission power of carrier wave is 50KW what will be the transmission power if the modulation is 80%

asked Mar 17, 2014 by sreemathi.v

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The population in a particular area is 1000 per square kilometer.What should be the height of the transmission tower to cover a population of 10 lakhs. For the sake of simplicity, assume that the Radius of earth is 6,400 Km.

asked Mar 17, 2014 by sreemathi.v

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What is the length of half wave dipole antenna at 100MHz

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The range of frequency used in television broadcasting is

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Critical frequency $\nu_c$ for ionsphere is

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The basic radio antenna is a metal rod,the length of which is

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Bandwidth is dependent on

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For commercial FM-transmission maximum frequency deviation allowed is

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In frequency modulation (FM) the

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In which of the following remote sensing technique is not used

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An oscillator is producing FM waves of frequency 3KHz with a variation of 9KHz what is the modulating index

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A carrier wave is modulated to 75%.If the power of carrier wave is 500W what is power of modulated wave

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An audio frequency of $4\times 10^3$ Hz is used to modulate a carrier wave of frequency 1MHz.The band width is

asked Mar 17, 2014 by sreemathi.v

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A amplitude modulated wave has maximum amplitude of 700mV and minimum amplitude of 200mV.Calculate the modulation factor

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A TV tower has a height of 100m.If the coverage range is to be made three times then by how much should the height of the tower be increased.

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A beam of electrons travels at $3 \times 10^{6} m/s$ through a uniform magnetic field of $4 \times 10^{-2} T$ at right angles to the field, as shown in the figure. How strong is the force acting on each electron?

asked Mar 14, 2014 by balaji.thirumalai

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Suppose a magnet is suspended by a vertical string, attached to its middle point. Given that the horizontal component of earth's magnetic field is $25\;\mu T$ and the vertical component of of earth's magnetic field is $40\;\mu T$ , find the position in which the magnet can stay in equilibrium.

asked Mar 14, 2014 by balaji.thirumalai

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Find the magnetic field at point P in the figure below, where I = 15 A and R = 20 cm.

asked Mar 14, 2014 by balaji.thirumalai

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A solenoid is 2.7-m long, has a radius of 0.85 cm, and has 600 turns. It carries a current I of 2.5 A. What is the magnitude of the magnetic field B inside the solenoid and far from either end?

asked Mar 14, 2014 by balaji.thirumalai

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A AM broadcasting station has a vertical telescopic transmitting antenna and a receiver has vertical telescopic antenna.The receiver will respond to

asked Mar 14, 2014 by sreemathi.v

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SKIP ZONE in radio wave transmission is that range where

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Which of the following is not an advantage of FM over AM

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Which of the following frequency will be suitable for beyond the horizon communication using sky waves?

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Frequencies in the UHF range are normally propagated by means of

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Over modulation results in

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In AM wave useful power is carried by

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Nature of analog signal is

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The length of half wave dipole antenna needed for a 200MHz signal is

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1 answer

The maximum distance upto which TV transmission from a TV tower of height 'h' can be received is proportional to

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