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प्रश्न
Describe the following term briefly:
minority carrier injection in forward biasing.
Explain the following term:
minority carrier injection in forward bias
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उत्तर
Due to the applied voltage, electrons from the n-side cross the depletion region and reach the p-side (where they are minority carriers). Similarly, holes from the p-side cross this junction and reach the n-side (where they are minority carriers). This process under forward bias is known as minority carrier injection.
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संबंधित प्रश्न
In the following diagram, is the junction diode forward biased or reverse biased ?
Draw a labelled diagram of a full wave rectifier. Show how output voltage varies with time if the input voltage is a sinusoidal voltage.
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- Electrons crossover from emitter to collector.
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- large velocity of the minority charge carriers if the doping concentration is small.
- large velocity of the minority charge carriers if the doping concentration is large.
- strong electric field in a depletion region if the doping concentration is small.
- strong electric field in the depletion region if the doping concentration is large.
Read the following paragraph and answer the questions that follow.
| A semiconductor diode is basically a pn junction with metallic contacts provided at the ends for the application of an external voltage. It is a two-terminal device. When an external voltage is applied across a semiconductor diode such that the p-side is connected to the positive terminal of the battery and the n-side to the negative terminal, it is said to be forward-biased. When an external voltage is applied across the diode such that the n-side is positive and the p-side is negative, it is said to be reverse-biased. An ideal diode is one whose resistance in forward biasing is zero and the resistance is infinite in reverse biasing. When the diode is forward biased, it is found that beyond forward voltage called knee voltage, the conductivity is very high. When the biasing voltage is more than the knee voltage the potential barrier is overcome and the current increases rapidly with an increase in forward voltage. When the diode is reverse biased, the reverse bias voltage produces a very small current of about a few microamperes which almost remains constant with bias. This small current is a reverse saturation current. |
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(b) 20 mA
(c) 35 mA
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(a)
(b)
(c)
(d)
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(a) bilateral device
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OR
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(a) in the circuits (1) and (2)
(b) in the circuits (2) and (3)
(c) in the circuits (1) and (3)
(d) only in the circuit (1) 
The V-I characteristic of a diode is shown in the figure. The ratio of the resistance of the diode at I = 15 mA to the resistance at V = -10 V is
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(b) 106
(c) 10
(d) 10-6
