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Choose the correct option. Current through a reverse-biased p-n junction increases abruptly at: - Physics

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प्रश्न

Choose the correct option.

Current through a reverse-biased p-n junction increases abruptly at:

विकल्प

  • Breakdown voltage

  • 0.0 V

  • 0.3V

  • 0.7V

MCQ

उत्तर

Current through a reverse-biased p-n junction increases abruptly at: Breakdown voltage

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p-n Junction
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अध्याय 14: Semiconductors - Exercises [पृष्ठ २५६]

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बालभारती Physics [English] 11 Standard Maharashtra State Board
अध्याय 14 Semiconductors
Exercises | Q 1. iii) | पृष्ठ २५६

संबंधित प्रश्न

In an unbiased p-n junction, holes diffuse from the p-region to n-region because ______.


In a p-n junction diode, the current I can be expressed as

I = `"I"_0 exp ("eV"/(2"k"_"BT") - 1)`

where I0 is called the reverse saturation current, V is the voltage across the diode and is positive for forward bias and negative for reverse bias, and I is the current through the diode, kBis the Boltzmann constant (8.6×10−5 eV/K) and T is the absolute temperature. If for a given diode I0 = 5 × 10−12 A and T = 300 K, then

(a) What will be the forward current at a forward voltage of 0.6 V?

(b) What will be the increase in the current if the voltage across the diode is increased to 0.7 V?

(c) What is the dynamic resistance?

(d) What will be the current if reverse bias voltage changes from 1 V to 2 V?


A zener diode is fabricated by heavily doping both p- and n- sides of the junction. Explain, why?


Explain briefly with the help of necessary diagrams, the forward biasing of a p-n junction diode. Also draw characteristic curves.


Explain briefly with the help of necessary diagrams, the  reverse biasing of a p-n junction diode. Also draw characteristic curves.


Mention the important considerations required while fabricating a p-n junction diode to be used as a Light Emitting Diode (LED). What should be the order of band gap of an LED if it is required to emit light in the visible range?


Explain, with the help of a circuit diagram, the working of n-p-n transistor as a common emitter amplifier.


When a p-type impurity is doped in a semiconductor, a large number of holes are created, This does not make the semiconductor charged. But when holes diffuse from the p-side to the n-side in a p-n junction, the n-side gets positively charged. Explain.


In a p-n junction with open ends,
(a) there is no systematic motion of charge carries
(b) holes and conduction electrons systematically go from the p-side to n-side and from the n-side to p-side respectively

(c) there is no net charge transfer between the two sides
(d) there is a constant electric field near the junction.


In a p-n junction,
(a) new holes and conduction electrons are produced continuously throughout the material
(b) new holes and conduction electrons are produced continuously throughout the material except in the depletion region
(c) holes and conduction electrons recombine continuously throughout the material
(d) holes and conduction electrons recombine continuously throughout the material except in the depletion region.


The potential barrier existing across an unbiased p-n junction is 0.2 volt. What minimum kinetic energy a hole should have to diffuse from the p-side to the n-side if (a) the junction is unbiased, (b) the junction is forward-biased at 0.1 volt and (c) the junction is reverse-biased at 0.1 volt?  


When a p-n junction is reverse-biased, the current becomes almost constant at 25 µA. When it is forward-biased at 200 mV, a current of 75 µA is obtained. Find the magnitude of diffusion current when the diode is
(a) unbiased,
(b) reverse-biased at 200 mV and
(c) forward-biased at 200 mV.


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.)


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.


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.)


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.)


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?


An AC source is connected to a diode and a resistor in series. Is the current thorough the resistor AC or DC?


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 __________ .


Answer in detail.

Discuss the effect of external voltage on the width of depletion region of a p-n junction.


If in a p-n junction diode, a square input signal of 10 V is applied as shown Then the output signal across RL will be ______

 


In a semiconductor diode, the barrier potential offers opposition to only ______.


Zener breakdown occurs in a p-n junction having p and n both:


The formation of the depletion region in a p-n junction diode is due to ______.


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