126. Direct conversion of solar energy with the use of photovoltaic cell results in the production of

1. 1. Optical energy

   
   
   

   2. Electrical energy

   
   
   

   3. Thermal energy

   
   
   

   4. Mechanical energy

   
   
   

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   NA

   Correct Option: B

   NA

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127. Energy is continuously generated in the sun due to

1. 1. Nuclear fusion

   
   
   

   2. Nuclear fission

   
   
   

   3. Radioactivity

   
   
   

   4. Artificial radioactivity

   
   
   

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   NA

   Correct Option: A

   NA

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128. The phenomenon of ejection of electrons from the surface of metals, when light of suitable wavelength falls on it, is known as

1. 1. Electrolysis

   
   
   

   2. Ionization

   
   
   

   3. Photo electric effect

   
   
   

   4. None of these

   
   
   

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   NA

   Correct Option: C

   NA

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129. Which of the following phenomena is observed when black discharge occurs in a discharge tube ?

1. 1. The wall of the tube opposite to the cathode glow

   
   
   

   2. Striations are seen

   
   
   

   3. A glow appears at the cathode

   
   
   

   4. Positive column appears

   
   
   

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   NA

   Correct Option: A

   NA

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130. In a discharge tube, ionization of enclosed gas is produced due to collisions between

1. 1. Neutral gas atoms / molecules

   
   
   

   2. Positive ions and neutral atoms / molecules

   
   
   

   3. Negative electrons and neutral atoms / molecules

   
   
   

   4. Photons and neutral atoms / molecules

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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