Can the potential barrier across a p-n junction be measured by simply connecting a voltmeter across the junction?
No, we cannot measure the potential barrier across the p-n junction by a voltmeter as this potential is only in the depletion region due to the electric field in that region. The rest of the crystals are insulator and thus block this electric field and as the voltmeter is connected across the diode, the barrier potential would not be measured.
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(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