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The drift current in a p-n junction is 20.0 µA. Estimate the number of electrons crossing a cross section per second in the depletion region.
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The current−voltage characteristic of an ideal p-n junction diode is given by \[i = i_0 ( e^{eV/KT} - 1)\] where, the drift current i0 equals 10 µA. Take the temperature T to be 300 K. (a) Find the voltage V0 for which \[e^{eV/kT} = 100 .\]One can neglect the term 1 for voltages greater than this value. (b) Find an expression for the dynamic resistance of the diode as a function of V for V > V0. (c) Find the voltage for which the dynamic resistance is 0.2 Ω.
(Use Planck constant h = 4.14 × 10-15 eV-s, Boltzmann constant k = 8·62 × 10-5 eV/K.)
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Consider a p-n junction diode having the characteristic \[i - i_0 ( e^{eV/kT} - 1) \text{ where } i_0 = 20\mu A\] . The diode is operated at T = 300 K . (a) Find the current through the diode when a voltage of 300 mV is applied across it in forward bias. (b) At what voltage does the current double?
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Calculate the current through the circuit and the potential difference across the diode shown in figure. The drift current for the diode is 20 µA.
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Each of the resistance shown in figure has a value of 20 Ω. Find the equivalent resistance between A and B. Does it depend on whether the point A or B is at higher potential?
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Find the currents through the resistance in the circuits shown in figure.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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What are the readings of the ammeters A1 and A2 shown in figure. Neglect the resistance of the meters.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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Find the current through the battery in each of the circuits shown in figure.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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Find the current through the resistance R in figure if (a) R = 12Ω (b) R = 48Ω.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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Draw the current-voltage characteristics for the device show in figure between the terminals A and B.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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Find the equivalent resistance of the network shown in figure between the points A and B.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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When the base current in a transistor is changed from 30µA to 80µA, the collector current is changed from 1.0 mA to 3.5 mA. Find the current gain β.
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A load resistor of 2kΩ is connected in the collector branch of an amplifier circuit using a transistor in common-emitter mode. The current gain β = 50. The input resistance of the transistor is 0.50 kΩ. If the input current is changed by 50µA. (a) by what amount does the output voltage change, (b) by what amount does the input voltage change and (c) what is the power gain?
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As the speed of a particle increases, its rest mass _______________ .
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An AC source is connected to a diode and a resistor in series. Is the current thorough the resistor AC or DC?
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A diode, a resistor and a 50 Hz AC source are connected in series. The number of current pulses per second through the resistor is __________ .
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Plot a graph to show the variation of stopping potential with frequency of incident radiation in relation to photoelectric effect.
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Work function of aluminium is 4.2 eV. If two photons each of energy 2.5 eV are incident on its surface, will the emission of electrons take place? Justify your answer.
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The stopping potential in an experiment on photoelectric effect is 1.5V. What is the maximum kinetic energy of the photoelectrons emitted? Calculate in Joules.
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How does the resistivity of a semiconductor change with rise of temperature ? Explain.
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