PN Junction

Q.

What causes the depletion region?

Q. (i) Explain with the help of a diagram, the formation of depletion region and barrier potential in a p-n junction.

(ii) Draw the circuit diagram of a half wave rectifier and explain its working.

Q. Which one of the following circuits shows correct biasing of a $\text{PNP}$ transistor to operate in the active region in the $\text{CE}$-mode-

1. 
2. 
3. 
4. 

Q. If $V_1>V_2$ , $r$ is the resistance offered by the diode in forward bias then current through the diode is

1. $0$
2. $\frac{V_1+V_2}{R+r}$
3. $\frac{V_1-V_2}{R+r}$
4. $\frac{V_1+V_2}{R}$

Q. The first ionization potentials (eV) of Be and B respectively are??How to calculate it?

Q. In a forward biased p- n junction diode, the potential barrier in the depletion region is of the form:

1. 
2. 
3. 
4. 

Q. 123.Potential difference across AB in the network shown in figure is

Q. In which type of connections of P-N junction, is the net flow holes from N-region to the P-region ?

1. forward
2. reverse
3. both 1 and 2
4. none of the above

Q.

When a forward bias is applied to a p-n junction, it

(a) raises the potential barrier.

(b) reduces the majority carrier current to zero.

(c) lowers the potential barrier.

(d) None of the above.

Q. (a) In the following diagram, is the junction diode forward biased or reverse biased ?

(b) Draw the circuit diagram of a full wave rectifier and state how it works.

Q. When a forward bias is applied to a p-n junction, it

1. raises the potential barrier.
2. reduces the majority carrier current to zero.
3. lowers the potential barrier.
4. None of the above.

Q. When p-n junction diode is forward biased then

1. the depletion region is reduced and barrier height is increased.
2. the depletion region is widened and barrier height is reduced.
3. both the depletion region and barrier height are reduced.
4. both the depletion region and barrier height are increase.

Q. The drift current in a reverse-biased p-n junction is increased in magnitude if the temperature of the junction is increased. Explain this on the basis of creation of hole-electron pairs.

Q.

diffusion current in a pn junction is greater than the drift current in magnitude if the junction is?

Q. what is the difference between barrier height and width of depleation region in semiconductors

Q. when p-n junction diode is forward biased what happens to the barrier height and depletion region?

Q.

doesnt a heavily doped pn junction diode have a thin potential barrier?

Q.

List the factors on which the width of depletion region depends.

Q.

When a forward bias is applied to a p-n junction, it

1. Raises the potential barrier

2. Reduces the majority carrier current to zero

3. None of the these

4. Lowers the potential barrier

Q. 1) What is Barrier Electric Field ??
2) What is Barrier Potential Difference ??

Q. The amplification factor of a triode operating in the linear region depends strongly on
(a) the temperature of the cathode
(b) the plate potential
(c) the grid potential
(d) the separations of the grid from the cathode and the anode