126. The magnifying power of the objective and eye-piece of a compound microscope are m₁ and m₂ The magnifying power of the microscope will be

1. 1. m₁ + m₂

   
   
   

   2. m₁ / m₂

   
   
   

   3. m₁ - m₂

   
   
   

   4. m₁ . m₂

   
   
   

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   N/A

   Correct Option: D

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127. Two sources of light are said to be coherent if the waves prouced by them have the same

1. 1. Wavelength

   
   
   

   2. Amplitude

   
   
   

   3. Wavelength and amplitude

   
   
   

   4. Wavelength and a constant phase difference

   
   
   

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   N/A

   Correct Option: D

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128. The illumination from the sun is greater at noon than in the evening because

1. 1. The sun is brighter at noon

   
   
   

   2. The sun is nearer to the earth at noon

   
   
   

   3. The rays of the sun are less oblique at noon that in the morning

   
   
   

   4. None of the above

   
   
   

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   N/A

   Correct Option: C

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129. Luminous intensity of a source is defined as

1. 1. Light energy emitted by the same source per unit time

   
   
   

   2. Light energy emitted by the source per unit time per unit area

   
   
   

   3. Light energy emitted by the source per unit time per unit solid angle

   
   
   

   4. None of the above

   
   
   

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   N/A

   Correct Option: C

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130. Suppose a rocket ship is receding from the earth at a speed of 2 / 10 th the velocity of light. A light in the rocket ship appears blue to the passengers on the ship. What colour would it appear to an observer on the earth ?

1. 1. Blue

   
   
   

   2. Orange

   
   
   

   3. Yellow

   
   
   

   4. Yellow-orange

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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