Which of the following statement are true for metal?
(i) Valence band overlaps with conduction bands.
(ii) The gap between valence band and conduction band is negligible.
(iii) The gap between valence band and conduction band cannot be determined.
(iv) Valence band may remain partially filled.
Question 2
When an alternating voltage of a given frequency is applied to a dielectric material, dissipation of energy occurs due to
1) Continual change in the orbital paths of the electrons in the atomic structure.
2) A small conduction current through the dielectric
3) Eddy currents Which of the above statements are correct?
Question 3
Which of the following statements regarding superconducting materials correct, when a large number of metals become superconducting below a temperature?
1) The resistivity ρ of the superconductor is zero.
2) The magnetic flux density B vanishes through the substance.
3) Ferromagnetic and Antiferromagnetic metals and good examples of superconducting materials.
Question 4
The value of hall coefficient is positive for
1) Intrinsic semiconductor
2) Metals
3) P-type semiconductor
4) N-type semiconductor
Question 5
Soft magnetic materials should have
Question 6
Above the Curie temperature, ferro-magnetic materials behave like
Question 7
The current flow in a semiconductor is due to 1) Drift current 2) Displacement current 3) Diffusion current
Question 8
What is the packing fraction of a BCC (body-centered cubic) unit cell?
Question 9
If the domain walls in a magnetic materials can easily be moved, the material displays