Q.1
Due to which of the following reasons aluminium does not corrode in atmosphere ?
Q.2
Which of the following high resistance materials has the highest operating temperature ?
Q.3
Which of the following material is not a semiconductor ?
Q.4
Steel wire is used as
Q.5
In thermocouples which of the following pairs is commonly used ?
Q.6
The transition temperature of mercury is
Q.7
Which of the following materials is preferred for transmitting electrical energy over long distance ?
Q.8
If the resistance of a conductor does not vary in accordance with Ohm’s law it is known as
Q.9
The forbidden gap in an insulator is
Q.10
Platinum is used in
Q.11
At transition temperature the value of critical field is
Q.12
The covalent bond is formed by
Q.13
The formula __________ determines the number of electrons that can be accommodated in any level.
Q.14
The superconductivity is due to
Q.15
Overhead telephone wires are made of
Q.16
Solder is an alloy of
Q.17
_________ is most commonly used for making magnetic recording tape
Q.18
A good electric contact material should have all of the following properties except
Q.19
Carbon resistors are used extensively because they are
Q.20
The current due to electron flow in conduction band is the hole current in valence band.
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