86. A light wave travelling in a transparent homogeneous medium enters another homogeneous transparent medium of higher refractive index. The speed of light in the second medium

1. 1. Is less than that in the first medium

   
   
   

   2. Is more than that in the first medium

   
   
   

   3. Is the same as that in the first medium

   
   
   

   4. May be more or less than that in the first medium depending on the angle of incidence

   
   
   

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   N/A

   Correct Option: A

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87. 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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   N/A

   Correct Option: A

   N/A

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88. In the human eye, the focussing is done by

1. 1. To and fro movement of the eye lens

   
   
   

   2. To and fro movement of the retina

   
   
   

   3. Change in the convexity of the eye lens

   
   
   

   4. Change in the refractive index of the eye fluids

   
   
   

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   N/A

   Correct Option: C

   N/A

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89. Th plane mirrors A and B are placed at a distance 12 cm apart facing towards each other. An object is placed in between them at a distance 8 cm from the mirror A. What will be the distance between them at a distance 8 cm from the mirror A. What will be the distance between the first two images, formed in the mirror B?

1. 1. 4 cm

   
   
   

   2. 8 cm

   
   
   

   3. 16 cm

   
   
   

   4. 20 cm

   
   
   

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   N/A

   Correct Option: C

   N/A

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90. Rainbow is formed due to a combination of

1. 1. Dispersion and total internal reflection

   
   
   

   2. Refraction and absorption

   
   
   

   3. Dispersion and focussing

   
   
   

   4. Refraction and scattering

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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