Which one of the following is the weakest kind of the bonding in solids?
Ionic
Metallic
Van der Waals'
Covalent
A semiconducting device is connected in a series in circuit with a battery and a resistance. A current is allowed to pass through the circuit. If the polarity of the battery is reversed, the current drios to almost zero. The device may be
a p-n junction
an intrinsic semiconductor
a p-type semiconductor
an n-type semiconductor
emitter
base
collector
Any of the above depending upon the nature of transistor.
Phosphorus
Aluminium
Magnesium
Both (b) and (c)
The transfer ratio β of a transistor is 50. The input resistance of the transistor when used in the common emitter configuration is 1kΩ. The peak value of the collector AC current for an AC input voltage of 0.01V peak is
100 μA
0.01 mA
0.25 mA
500 μA
When a triode is used as an amplifier the phase difference between the input signal voltage and the output is
zero
Which of the following when added as an impurity into silicon produces n-type semiconductor?
P
Al
B
Mg
The following truth table belongs to which of the following four gates?
NOR
XOR
NAND
OR
The current gain for a transistor working as common base amplifier is 0.96. If the emitter current is 7.2 mA, then the base current is
To obtain a p-type germanium semiconductor, it must be doped with
phosphorus
indium
antimony
arsenic