# Physics Ch 5 Class 12 Alternating Current

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If a half wave rectifier is used to convert 50Hz AC into DC, then the number of pulses present in rectified voltage is:

PMC Sample 1
Physics
Alternating Current
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Wavelength of X-rays is of the order of?

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Reactance of an Inductor Is given by:

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The angle made by the coil of an AC generator at a time Interval 3T/4 is?

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In a pure resistive circuit current and voltage are

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A circuit that adds positive or negative D.C. voltage to an input sine wave is called:

PMC Practice 4
Physics
Alternating Current
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Step up transformer have ________ turns in secondary coil.

PMC Practice 1
Physics
Alternating Current
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In a full-wave rectification, the number of diodes used are:

PMC 2020
Physics
Alternating Current
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Power factor in an AC circuit Is?

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X-rays have frequency greater than

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In a half wave rectifier, the diode conducts during:

NUMS 2019 Reconduct
Physics
Alternating Current
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The AC generator is similar to:

PMC 2021 Tested
Physics
Alternating Current
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If the instantaneous current in a circuit is given by I = A sin (wt) ampere, the RMS value of the current is:

PMC Practice 3
Physics
Alternating Current
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What is the instantaneous power dissipated through a resistor of resistance 10 ohm if it is connected to an AC source of frequency 15 Hz at 1/180 sec if peak value is 20 V?

UHS 2018
Physics
Alternating Current
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Electromagnetic waves are produced due to flow of

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An Inductor of 1H Is connected across a 220V, 50Hz supply. The peak value of current is approximately:

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Alternating Current Generators use:

PMC Practice 5
Physics
Alternating Current
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In case of half wave rectification the resistance of diode during negative half of A.C is:

UHS 2018
Physics
Alternating Current
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An alternation voltage V (in volts) is represented by the equation:
V = 300 sin (100πt)
What is the value of “f” for this voltage?

UHS 2019
Physics
Alternating Current
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A full wave rectifier is operating from 50 Hz mains. Fundamental frequency of ripple will be:

PMC Practice 1
Physics
Alternating Current
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If an AC voltage of rms value of 10 volts is applied as input of a half-wave rectifier, then the voltage value of the DC output will be:

PMC Practice 4
Physics
Alternating Current
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PIV stands for :

PMC 2020
Physics
Alternating Current
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P = Irms Vrms Is applicable for

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In a step up transformer ________.

NTS 2019
Physics
Alternating Current
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that the supply for the potentiometer is taken?

PMC Practice 8
Physics
Alternating Current
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Which of the following remains unchanged in a transformer.

PMC Sample 3
Physics
Alternating Current
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The use of a capacitor filter in a rectifier circuit gives satisfactory performance only when the load:

PMC Practice 3
Physics
Alternating Current
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Power factor. of RLC circuit at Resonance Is

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For an ideal step-up transformer Ps ——- Pp.

PMC Practice 8
Physics
Alternating Current
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The maximum efficiency of a half-wave rectifier is:

PMC Practice 3
Physics
Alternating Current
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The principle of a capacitor is based on which of the following facts?

NTS 2011
Physics
Alternating Current
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In electronic circuits, a PN junction diode is used to convert alternating current into direct current. This process is called:

NTS 2018
Physics
Alternating Current
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RLC circuit can be excited by

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An alternating voltage source is connected to a resistor R, and a capacitor C, then which of the following statements about phase angle between voltage V and current I is correct?

NUMS 2019 Cancelled
Physics
Alternating Current
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Voltage after which in forward bias current start to rise with increase in voltage is called:

PMC Sample 3
Physics
Alternating Current
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The direction of current through the load resistance of a full-wave rectification circuit:

UHS 2019
Physics
Alternating Current
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Resistance of RCL series circuit at resonance Is?

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In RLC series circuit at resonance, the A.C voltage across Resistance R, Inductance L and capacitance C are 5V, 10V and 10 V respectively. The A.C voltage applied to the circuit will be:

NUMS 2015
Physics
Alternating Current
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A half wave rectifier is operating from 50 Hz mains, fundamental frequency of ripple will be

PMC Sample 3
Physics
Alternating Current
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In a practical transformer mutual induction between primary and secondary coils takes place. In such transformer what can be deduced about the power.

UHS 2018
Physics
Alternating Current
Work, Power & Energy
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The rectifier is a device which converts?

PMC Practice 3
Physics
Alternating Current
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Voltage Is current In RC circuit.

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Transformer is used in rectification to ___________ the supply voltage.

PMC Practice 5
Physics
Alternating Current
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