206. Which of the following statements is not true?

1. 1. Conductance is the reciprocal of resistance and is measured is siemens

   
   
   

   2. Ohm's law is not applicable at very low and very high temperature

   
   
   

   3. Ohm's law is applicable to semiconductor

   
   
   

   4. Ohm's law is not applicable to electron tubes, discharge tubes and electrolytes

   
   
   

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   NA

   Correct Option: C

   NA

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207. A point charge is brought in an electric. The field at a nearby point

1. 1. May increase if the charge is positive

   
   
   

   2. May decrease if the charge is negative

   
   
   

   3. Both (a) and (b)

   
   
   

   4. None of the above

   
   
   

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   NA

   Correct Option: C

   NA

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208. A proton, when accelerated through a potential difference of V volts, has an associated wavelength, an a-particle must be accelerated through a potential difference of

1. 1. V volts

   
   
   

   2. 4 V volts

   
   
   

   3. 2 V volts

   
   
   

   4. V / 8 volts

   
   
   

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   NA

   Correct Option: D

   NA

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209. A magnetic field

1. 1. Always exerts a force on a charged particle

   
   
   

   2. Never exerts a force on a charged particle

   
   
   

   3. Exerts a force on a charged particle if it is moving across the magnetic lines of force

   
   
   

   4. Never exerts a force on a charged particle if it is moving along the magnetic lines of force

   
   
   

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   NA

   Correct Option: C

   NA

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210. When a glass rod is rubbed with silk, both glass rod and silk

1. 1. Acquire equal and similar charges

   
   
   

   2. Acquire equal and opposite charges

   
   
   

   3. Acquire unequal and opposite charges

   
   
   

   4. Acquire unequal and similar charges

   
   
   

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   NA

   Correct Option: B

   NA

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