In a p-n junction diode not connected to any circuit:

1.	the potential is the same everywhere.
2.	the P-type is at higher potential than the N-type side.
3.	there is an electric field at the junction directed from the N- type side to the P- type side.
4.	there is an electric field at the junction directed from the P-type side to the N-type side.

Which of the following statements is not true

(1) The resistance of intrinsic semiconductors decrease with increase of temperature

(2) Doping pure with trivalent impurities give P-type semiconductors

(3) The majority carriers in N-type semiconductors are holes

(4) A PN-junction can act as a semiconductor diode

The dominant mechanisms for motion of charge carriers in forward and reverse biased silicon P-N junctions are

(1) Drift in forward bias, diffusion in reverse bias

(2) Diffusion in forward bias, drift in reverse bias

(3) Diffusion in both forward and reverse bias

(4) Drift in both forward and reverse bias

When a forward bias is applied to a p-n junction, then what happens to the potential barrier $V_{\mathit{B}}$, and the width of charge depleted region x?

When the P end of P-N junction is connected to the negative terminal of the battery and the N end to the positive terminal of the battery, then the P-N junction behaves like 

(1) A conductor                       

(2) An insulator
(3) A super-conductor             

(4) A semi-conductor

A potential barrier of 0.50 V exists across a P-N junction. If the depletion region is $5.0\times {10}^{-7}$m wide, the intensity of the electric field in this region is 
(1) $1.0\times {10}^6 \mathrm{V}/\mathrm{m}$                     

(2) $1.0\times {10}^5 \mathrm{V}/\mathrm{m}$
(3) $2.0\times {10}^5 \mathrm{V}/\mathrm{m}$                     

(4) $2.0\times {10}^6 \mathrm{V}/\mathrm{m}$

Barrier potential of a P-N junction diode does not depend on 

(1) Temperature               

(2) Forward bias
(3) Doping density             

(4) Diode design

Which is the correct diagram of a half-wave rectifier?

1. 

2. 

3. 

4. 

Zener breakdown takes place if 

(1) Doped impurity is low             

(2) Doped impurity is high
(3) Less impurity in N-part           

(4) Less impurity in P-type

Which one of the following statements is not correct

(1) A diode does not obey Ohm's law

(2) A PN junction diode symbol shows an arrow identifying the direction of current (forward) flow

(3) An ideal diode is an open switch

(4) An ideal diode is an ideal one way conductor