6. The relative permeability of a paramagnetic substance is :
(a) unity
(b) slightly more than unity
(c) zero
(d) less than unity
7. Ferroelectric materials are characterised by :
(a) Very high degree of polarisation
(b) A sharp dependence of polarisation on temperature
(c) Non-linear dependence of the charge Q on the applied voltage
(d) All the above
8. In a ferromagnetic material the state of flux density is as follows when external magnetic field is applied to it.
(a) Increased
(b) Decreased
(c) Remains unchanged
(d) Becomes zero
9. Magnetic materials :
(a) provide path to magnetic flux
(b) are good insulators
(c) are semiconductors
(d) None
10. Hard magnetic materials are used for making :
(a) Permanent magnets
(b) Temporary magnets
(c) Conductors
(d) Insulator
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