Q.1
The rule that resistivity of conductors can be separated into two parts viz. temperature independent and temperature dependent is known as
Q.2
When a material is in superconducting state and a magnetic field is applied
  • The superconducting property is not affected
  • The superconducting property may be affected and resistivity may increase from zero to a low value
  • The superconducting property may be destroyed
  • The material may become an insulator
Q.3
The unit for mmf is
  • A
  • Wb
  • T
  • V
Q.4
When a dielectric material is subjected to alternating field, the absorption of energy by the material from the field is given by the imaginary part of polarizability.
  • True
  • False
Q.5
The phenomenon of dielectric hysteresis occurs with
  • DC
  • AC
  • Both AC and DC
  • None of the above
Q.6
Hall effect is observed in a specimen (metal or semi conductor) when it is carrying current and is placed in a magnetic field. The resultant electric field inside the specimen is
  • Normal to both current and magnetic field
  • In the same direction as current
  • In a direction anti parallel to magnetic field
  • None of the above
Q.7
As the atoms of rare gases become larger, electronic polarizability
  • Increases
  • Decreases
  • Remains the same
  • May increase or decrease
Q.8
The residual resistivity of a binary alloy at 0 K is
  • Sum of residual resistivities of component metals
  • Difference of residual resistivities of component metals
  • Product of residual resistivities of component metals
  • Dependent on the concentration of minor component in the alloy
Q.9
Nickel is a non-magnetic material.
  • True
  • False
Q.10
The most important set of specifications of transformer oil include
  • dielectric strength and viscosity
  • dielectric strength and flash point
  • viscosity and flash point
  • flash point and viscosity
Q.11
If a small amount of Cu is added to Ni conductor, then
  • Resistivity of Ni will decrease at all temperatures because Cu is a better conductor than Ni
  • Residual resistivity of Ni at low temperature will increase as Cu atoms act as defect centres
  • Resistivity of Ni will increase at all temperatures as Cu destroys the periodicity of Ni and acts as defects
  • Resistivity of Ni remains the same
Q.12
The fact that domains exhibits spontaneous magnetisation is
  • First hypothesis is of Curie
  • Second hypothesis is of Weiss
  • Curie-Weiss law
  • Boltzmann’s statistics
Q.13
The number of protons in a silicon atom are
  • 4
  • 8
  • 12
  • 14
Q.14
The elements which become superconducting at extremely low temperatures are
  • Good conductors at room temperature
  • Ferromagnetic at room temperature
  • Relatively poor conductors at room temperature
  • Insulators at room temperature
Q.15
If the number of atoms per unit volume of a monoatomic gas changes, the dielectric constant still remains constant.
  • True
  • False
Q.16
With increase in temperature, the electrical conductivity would
  • Increase in metals as well as in intrinsic semiconductor
  • Increase in metals but decrease in intrinsic semiconductor
  • Decrease in metals but increase in intrinsic semiconductor
  • Decrease in metals as well as in intrinsic semiconductor
Q.17
The number of protons in a copper atom are
  • 2
  • 9
  • 11
  • 29
Q.18
Wood is a diamagnetic material.
  • True
  • False
Q.19
In a metal, the valence electrons
  • Are not shared
  • Are shared only between neighbouring atoms
  • Are shared by all atoms
  • Either B or C
Q.20
Ferrimagnetic materials have anti parallel orientation of equal moments of permanent dipoles.
  • True
  • False
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