221. A ferroelectric material exhibits:

1. 1. spontaneous magnetisation

   
   
   

   2. hysteresis effect with polarization

   
   
   

   3. no spontaneous magnetisation

   
   
   

   4. superconducting states

   
   
   

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1. View Hint View Answer Discuss in Forum

   A ferroelectric material exhibits hysteresis effect with polarization.

   Correct Option: B

   A ferroelectric material exhibits hysteresis effect with polarization.

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222. Piezoelectricity has been observed in:

1. 1. nickel

   
   
   

   2. glass

   
   
   

   3. quartz

   
   
   

   4. mica

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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223. Displacement current in a dielectric primarily depends upon the:

1. 1. resistivity

   
   
   

   2. dipole moment

   
   
   

   3. frequency of operating field

   
   
   

   4. mobility

   
   
   

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1. View Hint View Answer Discuss in Forum

   Displacement current in a dielectric primarily depends upon the dipole moment.

   Correct Option: B

   Displacement current in a dielectric primarily depends upon the dipole moment.

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224. Which of the following pairs are correctly matched?
     

     1. Steatite	:	Magnesia-silica ceramic dielectric resistivity
     2. Discharge	:	Gas bubbles are responsible breakdown for it
     3. Dielectric loss	:	It decreases with decrease in humidity
     4. FerroelectricCurie temperature	:	It is related to both ferromagnetic and ferroelectric materials

     
     Select the correct answer using the codes given below:

1. 1. 2, 3 and 4

   
   
   

   2. 1, 3 and 4

   
   
   

   3. 1 and 3

   
   
   

   4. 1, 2 and 4

   
   
   

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1. View Hint View Answer Discuss in Forum

   * Steatite	→	Magnesia-silica ceramic dielectric.
   * Discharge breakdown	→	Gas bubbles are responsible for it.
   * Ferroelectric Curie temperature	→	It is related to both ferromagnetic and ferroelectric materials.

   Correct Option: D

   * Steatite	→	Magnesia-silica ceramic dielectric.
   * Discharge breakdown	→	Gas bubbles are responsible for it.
   * Ferroelectric Curie temperature	→	It is related to both ferromagnetic and ferroelectric materials.

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225. The microstructure composition of pearlite for an Fe₃C diagram consists of:

1. 1. carbon dissolved in alpha iron having a body centred cubic structure

   
   
   

   2. carbon dissolved in gamma iron having a bodycentred cubic structure

   
   
   

   3. a mixture of body-centred alpha having a facecentred gamma iron

   
   
   

   4. carbon dissolved in body-centred alpha iron and an Fe₃C compound of higher carbon

   
   
   

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1. View Hint View Answer Discuss in Forum

   The microstructure composition of pearlite for an Fe₃C diagram consists of carbon dissolved in body-centred alpha iron and an Fe₃C compound of higher carbon.

   Correct Option: D

   The microstructure composition of pearlite for an Fe₃C diagram consists of carbon dissolved in body-centred alpha iron and an Fe₃C compound of higher carbon.

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