26. The image of an object formed by device is always virtual and small. The device may be

1. 1. Convex lens

   
   
   

   2. Concave mirror

   
   
   

   3. Concave lens

   
   
   

   4. None of these

   
   
   

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   N/A

   Correct Option: C

   N/A

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27. When a ray of light enters a water filled glass tank from a glass face making a non zero angle to the normal, the emergent ray from the opposite face will follow a path which is

1. 1. Same

   
   
   

   2. Deflected to the right

   
   
   

   3. Deflected to the left

   
   
   

   4. Parallel but not same

   
   
   

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   N/A

   Correct Option: D

   N/A

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28. If the refractive angle of a prism is 60° and the minimum deviation is 30°, then the angle of incidence is

1. 1. 30°

   
   
   

   2. 60°

   
   
   

   3. 45°

   
   
   

   4. 90°

   
   
   

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   N/A

   Correct Option: C

   N/A

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29. The refractive index of a piece of transparent quartz is the greatest for

1. 1. Red light

   
   
   

   2. Yellow light

   
   
   

   3. Green light

   
   
   

   4. Violet light

   
   
   

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   N/A

   Correct Option: D

   N/A

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30. Two sources of wave are called coherent if

1. 1. Both have the same amplitude of vibration

   
   
   

   2. Both produce waves of the same wavelength

   
   
   

   3. Both produce waves of the same wavelength having a constant phase difference

   
   
   

   4. Both produce waves having the same velocity

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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