11. A Swimming pool looks shallower than it really is, when see by a person standing outside near it, because of the phenomenon of

1. 1. refraction of light

   
   
   

   2. reflection of light

   
   
   

   3. dispersion of light

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   refraction of light

   Correct Option: A

   refraction of light

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12. A student finds the writing on the black board as blurred and unclear when sitting on the last desk in a classroom. However, he sees it clearly when sitting on the front desk. Student suffers from a vision defect known as

1. 1. hypermetropia

   
   
   

   2. myopia

   
   
   

   3. presbyopia

   
   
   

   4. astigmatism

   
   
   

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1. View Hint View Answer Discuss in Forum

   Myopic eye can see near objects clearly but cannot see far objects clearly.

   Correct Option: B

   Myopic eye can see near objects clearly but cannot see far objects clearly.

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13. Which one among the following is the correct order of power consumption for light of equal intensity ?

1. 1. CFL tube < Fluorescent tube < Incandescent bulb < Light emitting diode

   
   
   

   2. Light emitting diode < CFL tube < Fluorescent tube < Incandescent bulb

   
   
   

   3. CFL tube < Fluorescent tube < Light emitting diode < Incandescent bulb

   
   
   

   4. Incandescent bulb < Light emitting diode < Fluorescent tube < CFL tube

   
   
   

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1. View Hint View Answer Discuss in Forum

   Light emitting diode < CFL tube < fluorescent tube < Incandescent bulb

   Correct Option: B

   Light emitting diode < CFL tube < fluorescent tube < Incandescent bulb

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14. Which one of the following is correct? Lightning is formed, when

1. 1. similar charges of electricity rush towards each other and then get repelled

   
   
   

   2. clouds strike against impurities in air and the friction burns up these impurities

   
   
   

   3. strong opposite charges in different clouds break down the resistance offered by intervening air

   
   
   

   4. water vapor produces electricity in the clouds

   
   
   

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1. View Hint View Answer Discuss in Forum

   strong opposite charges in different clouds break down the resistance offered by intervening air

   Correct Option: C

   strong opposite charges in different clouds break down the resistance offered by intervening air

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15. When light passes from one medium to another medium, which one of the following does not change?

1. 1. Instensity

   
   
   

   2. Velocity

   
   
   

   3. Wavelength

   
   
   

   4. Frequency

   
   
   

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1. View Hint View Answer Discuss in Forum

   When light passes from one medium to another medium frequency does not change.

   Correct Option: B

   When light passes from one medium to another medium frequency does not change.

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