91. Assertion (A): Small glass beads fixed on traffic signal glow brightly when light falls upon them.
    Reason (R) : Light is totally reflected when the angle of incidence exceeds a certain critical value and light travelling in a denser medium is reflected from a rarer medium.
    Codes:

1. 1. Both A and R are true and R is the correct explanation of A

   
   
   

   2. Both A and R are but R is not a correct explanation of A

   
   
   

   3. A is true but R is false

   
   
   

   4. A is false but R is true

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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92. To which one of the following processes is the term CMYK related ?

1. 1. Railway signaling

   
   
   

   2. Navigation

   
   
   

   3. Offset printing

   
   
   

   4. Electronic voting machine

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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93. A lens, immersed in a liquid becomes invisible when

1. 1. The focal length of the lens is zero

   
   
   

   2. The focal length of the lens is infinite

   
   
   

   3. The refractive index of the lens is less than the refractive index of the liquid

   
   
   

   4. The refractive index of the lens is equal to the refractive index of the liquid

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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94. To have larger magnification by a telescope

1. 1. The objective should be of large focal length and the eyepiece should be of small focal length

   
   
   

   2. Both the objective and eyepiece should be of small focal length

   
   
   

   3. Both the objective and the eyepiece should be large focal length

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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95. When a mirror is rotated by an angle θ, the reflected ray will rotated by

1. 1. 0°

   
   
   

   2. θ / 2

   
   
   

   3. θ

   
   
   

   4. 2 θ

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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