# Physics Ch 7 Class 12 Electronics

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Consider a peak rectifier fed by a 60-Hz sinusoid having a peak value Vp = 100V. Let the load resistance R = 10kΩ . Calculate the fraction of the cycle during which the diode is conducting:

PMC Practice 5
Physics
Electronics
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When semi-conductors dopped In
then they are p-type

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In a centre tap full wave rectifier if Vm is the peak voltage across the secondary of transformer, the maximum voltage across reverse bias is

PMC Practice 11
Physics
Electronics
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Majority charge carriers in P-type semiconductor are

PMC Sample 2
Physics
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In the breakdown region zener behaves like a

PMC Sample 2
Physics
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When reverse bias of a p-n junction diode is increased, a stage comes when electric field set up is sufficient to rupture covalent bonds and release a large number of holes and electrons. This breakdown phenomenon is known as:

NUMS 2018
Physics
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In full wave rectifier with input frequency 50 Hz the ripple in the output is mainly of frequency

PMC Practice 6
Physics
Electronics
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A negligible small current between input terminals of the operational amplifier is because of:

UHS 2019
Physics
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A full wave rectifier uses load resistor of 1500 Ω. Assume the diodes have Rf= 10 Ω, Rr= ∞. The voltage applied to diode is 30V with a frequency of S0Hz. Calculate the AC power input.

PMC Practice 14
Physics
Electronics
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If the temperature of diode increases the leakage current will

PMC Sample 2
Physics
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In half-wave rectification, the output DC voltage is obtained across the load for ______.

PMC Practice 9
Physics
Electronics
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Which two or more of the following actions would increase the energy stored in a parallel plate capacitor when a constant potential difference is applied across the plates:

PMC Practice 5
Physics
Electronics
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A full wave rectifier is operating from 50 Hz mains, fundamental frequency of ripple will be

PMC Sample 2
Physics
Electronics
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When an Operational amplifier is used as Inverting amplifier, then angle between its output and input signal is:

NUMS 2019 Cancelled
Physics
Electronics
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The process of converting alternating current to direct current is called?

PMC Practice 14
Physics
Electronics
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A type of metals containing alloys, ceramics etc., when heated their temperature reaches to a state called Transition temperature state and their resistance reaches to zero. These types of metals are called:

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Gamma rays are attracted towards

PMC Practice 11
Physics
Electronics
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Input resistance of an Operational Amplifier is:

NUMS 2019 Reconduct
Physics
Electronics
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Half wave voltage multiplier can provide any degree of voltage multiplication by cascading diodes and capacitors.

PMC Practice 12
Physics
Electronics
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Consider a peak rectifier fed by a 60-Hz sinusoid having a peak value Vp = 100 V. Let the load resistance R = 10 kΩ. Calculate the fraction of the cycle during which the diode is conducting:

PMC Practice 13
Physics
Electronics
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A signal of -80 mV is applied to the inverting terminal of the amplifier while the non inverting terminal is grounded. The gain of the amplifier is 25 using Rin(R1) equal to 3 ohms and Rf(R2) equal to 75 Ohms. What would be the value of the output signal?

UHS 2018
Physics
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The width of depletion region Increases due to:

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If the input frequency of a full-wave rectifier is 50 Hz, its ripple frequency is:

PMC 2021 Tested
Physics
Electronics
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______ is equivalent to AND Gate followed by a NOT Gate.

NUMS 2017
Physics
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If x and y are the input of the GATE, and z is the output, the following table represents:

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A capacitor and an inductor are connected to A.C. supply. If we double the frequency of A.C. supply then the effect on reactance of capacitor XC and reactance of inductor XL will be:

NUMS 2019 Cancelled
Physics
Electronics
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The number of diodes in centre-tapped full-wave rectifier is:

PMC 2021 Tested
Physics
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The open-circuit test in a transformer is used to measure?

PMC Practice 3
Physics
Electronics
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Which of the following is not a type of rectifier?

PMC Practice 12
Physics
Electronics
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Transistors can be used as:

PMC Practice 10
Physics
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Which of the following rectifier uses a wheatstone bridge to rectify signals?

PMC Practice 13
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A half-wave rectifier uses:

PMC Practice 13
Physics
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AC is converted to D.C by:

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Maximum efficiency of half wave rectifier is:

PMC Practice 11
Physics
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If peak voltage across a full wave rectifier is 20V then Vrms is:

PMC Practice 10
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The ripple factor of half-wave rectifier is?

PMC Practice 14
Physics
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In photodiodes, the bias voltage is applied in ______ bias form.

NTS 2016 DUHS & JSMU
Physics
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A logic gate has four inputs. Its possible input combinations will be:

NUMS 2015
Physics
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The half wave rectifier has how many diodes?

PMC 2021 Tested
Physics
Electronics
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The principle behind the working of cathode ray oscilloscope is:

PMC Sample 1
Physics
Electronics
Magnetism and Electromagnetic Induction
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At least how many diodes are required to covert A.0 fully into D.C?

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The basic purpose of filter is to?

PMC Practice 1
Physics
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The electron volt is the unit of __________.

PMC Practice 3
Physics
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In half wave rectification, the output DC voltage is obtained across the load for?

PMC Practice 10
Physics
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If both inputs “A” and “B” are ON and the output is also ON. This type of gate is known as:

NUMS 2017
Physics
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In a npn transistor, the current IEthat flows in the emitter circuit is:

NTS 2016 DUHS & JSMU
Physics
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A cable 4 km long and of total resistance 1 Ohm carries electric current from a generator producing 100kW at 10,000 Volts. The current in amperes in the cable is:

PMC Practice 5
Physics
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To get a peak load voltage of 40V out of a bridge rectifier, what should be the approximate rms value of secondary voltage?

PMC Practice 5
Physics
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A transistor cannot be used as

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In full wave rectifier with input frequency 50 Hz, the ripple in the output is mainly of frequency?

PMC Practice 10
Physics
Electronics
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Which of the following is a type of rectifier?

PMC Practice 15
Physics
Electronics
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Non-inverting amplifier circuits have?

PMC Practice 2
Physics
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A semiconductor photodiode is a:

NTS 2011
Physics
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