6. Current density in a conducting media is—

1. 1. J = nqµ

   
   
   

   2. J = σE a

   
   
   

   3. J = nµ E

   
   
   

   4. J = nqε
      

   
   
   

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   NA

   Correct Option: B

   NA

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7. Dynamic resistance of a diode varies as—

1. 1. I^–2

   
   
   

   2. I^–1

   
   
   

   3. I

   
   
   

   4. I²

   
   
   

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   Dynamic resistance of a diode varies as
   

   γf =	nVT
   	I

   
   i.e.

   γf =	1
   	I

   
   or γf varies as I^–1

   Correct Option: B

   Dynamic resistance of a diode varies as
   

   γf =	nVT
   	I

   
   i.e.

   γf =	1
   	I

   
   or γf varies as I^–1

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8. For a forward biased pn-junction diode diffusion capacitance varies—

1. 1. Linearly with current

   
   
   

   2. Square of current

   
   
   

   3. Inversely with current

   
   
   

   4. Does not vary with current

   
   
   

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   For a forward biased pn-junction diode diffusion capacitance varies linearly with current.

   Correct Option: A

   For a forward biased pn-junction diode diffusion capacitance varies linearly with current.

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9. The switching speed of pn-junction depends primarily on—

1. 1. Mobility of majority carriers in n-region

   
   
   

   2. Mobility of minority carriers in p-region

   
   
   

   3. Lifetime of minority carriers in p-region

   
   
   

   4. Lifetime of minority carriers in n-region

   
   
   

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   The switching speed of pn-junction depends primarily on lifetime of minority carriers in n-region.

   Correct Option: D

   The switching speed of pn-junction depends primarily on lifetime of minority carriers in n-region.

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10. Fermi level for an n-type semiconductor lies—

1. 1. Near valence band

   
   
   

   2. Near conduction band

   
   
   

   3. In valence band

   
   
   

   4. In conduction band

   
   
   

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1. View Hint View Answer Discuss in Forum

   Fermi level for an n-type semiconductor lies near conduction band.
   

   Correct Option: B

   Fermi level for an n-type semiconductor lies near conduction band.

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