Q. 105.0( 1 Vote )
Consider an npn transitor with its base-emitter junction forward biased and collector base junction reverse biased. Which of the following statements are true?.
A. Electrons crossover from emitter to collector.
B. Holes move from base to collector.
C. Electrons move from emitter to base.
D. Electrons from emitter move out of base without going to the collector.
When the base-emitter junction is forward biased, the negative pole of the battery is connected to the emitter and the positive pole is connected to the base. Therefore, the electrons flow from the emitter (negative pole) to the base (positive pole).
Similarly, when the collector base junction is reversed biased the electrons crossover from the emitter (negative pole) to the collector (positive pole).
Rate this question :
(a) A student wants to use two p-n junction diodes to convert alternating current into direct current. Draw the labelled circuit diagram she would use and explain how it works.
(b) Give the truth table and circuit symbol for NAND gate.Physics - Board Papers
(i) Explain with the help of a diagram the formation of depletion region and barrier potential in a pn junction.
(ii) Draw the circuit diagram of a half wave rectifier and explain its working.Physics - Board Papers
Write the two processes that take place in the formation of a p-n junction. Explain with the help of a diagram, the formation of depletion region and barrier potential in a p-n junction.Physics - Board Papers
Name the junction diode whose I-V characteristics are drawn below:
Physics - Board Papers
Using a suitable combination from a NOR, an OR and a NOT gate, draw circuits to obtain the truth tables given below:
Physics - Exemplar
What do the terms ‘depletion region’ and ‘barrier potential’ mean for a p-n junction?Physics - Exemplar
Consider a box with three terminals on top of it as shown in Fig.14.18 (a):
Three components namely, two germanium diodes and one resistor are connected across these three terminals in some arrangement.
A student performs an experiment in which any two of these three terminals are connected in the circuit shown in Fig. 14.18 (b).
The student obtains graphs of current-voltage characteristics for unknown combination of components between the two terminals connected in the circuit.
The graphs are
(i) when A is positive and B is negative
(ii) when A is negative and B is positive
(iii) When B is negative and C is positive
(iv) When B is positive and C is negative
(v) When A is positive and C is negative
(vi) When A is negative and C is positive
From these graphs of current – voltage characteristic shown in Fig. 14.18 (c) to (h), determine the arrangement of components between A, B and C.
Physics - Exemplar