146. When a ray of light emerges from a block of glass, the critical angle is

1. 1. Equal to the angle of reflection

   
   
   

   2. The angle between the reflected ray and the normal

   
   
   

   3. The angle of incidence for which the refracted ray travels along the glass air boundary

   
   
   

   4. The angle of incidence

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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147. As an object gets closer to the focal point of a converging lens from infinity, its image

1. 1. Becomes smaller

   
   
   

   2. Remains of the same size

   
   
   

   3. Gets farther from the lens

   
   
   

   4. Gets closer to the lens

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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148. If the top half of a convex lens is covered with black paper

1. 1. The bottom half of the image will disappear

   
   
   

   2. The top half of the image will disappear

   
   
   

   3. The magnification will reduced to half

   
   
   

   4. The intensity will be reduced to half

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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149. In a cinema hall, the distance between the projector and the screen is increased by 2% Then the intensity of illumination of the screen is

1. 1. Decreased by 2%

   
   
   

   2. Decreased by 4%

   
   
   

   3. Increased by 2%

   
   
   

   4. Increased by 4%

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

   N/A

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150. When a CD (compact disc used in audio and video systems) is seen in sunlight, Rainbow like colours are seen. This can be explained on the basis of the phenomenon of

1. 1. Reflection and diffraction

   
   
   

   2. Reflection and transmission

   
   
   

   3. Diffraction and transmission

   
   
   

   4. Refraction, diffraction and transmission

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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