176. To obtain a sustained interference pattern, we require two sources which emit radiation of

1. 1. The same frequency

   
   
   

   2. Nearly the same frequency

   
   
   

   3. The same frequency and have a definite phase relationship

   
   
   

   4. Different wavelengths

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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177. All of the following statements are correct except

1. 1. The magnification produced by a convex mirror is always less than one

   
   
   

   2. A virtual, erect, same sized, image can be obtained using a plane mirror

   
   
   

   3. A virtual, erect magnified image can be formed using a concave mirror

   
   
   

   4. A real, inverted, same sized image can be formed using a convex mirror

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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178. The refractive index of a medium is √3. Which one of the following is correct ?

1. 1. The sine of angle of incidence is √3 times the sine of angle of refraction

   
   
   

   2. The angle of incidence is twice the angle of refraction

   
   
   

   3. The sine of angle of refraction is √3 times the sine of angle of incidence

   
   
   

   4. The angle of refraction is twice the angle of incidence

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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179. Assertion (A): In the visible spectrum of light, red light is more energetic than green light.
     Reason (R) : The wavelength of red light is more than that of green light.
     Codes

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

   
   
   

   2. A and R are individually true but R is but the correct explanation of A

   
   
   

   3. A is true, but is false

   
   
   

   4. A is false, but is true

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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180. Which one of the following statements is correct ?
     In an astronomical telescope of refracting type

1. 1. The objective and the eyepiece have the same focal length

   
   
   

   2. The focal length of the objective is less than that of the eyepiece

   
   
   

   3. The focal length of the objective is more than that of the eyepiece

   
   
   

   4. The aperture of the eyepiece is more than that of the objective

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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