6. Consider the following statements :
   1. X - rays show transverse wave characteristics
   2. X - rays can eject electrons from certain metal surfaces
   3. X - rays of 0.1 A^° are harder than X - rays of 0.2 A^°
   Which of the statements given above is / are correct ?
   
   

1. 1. 1 only

   
   
   

   2. 1 and 2 only

   
   
   

   3. 2 an 3 only

   
   
   

   4. 1, 2 and 3

   
   
   

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   NA

   Correct Option: D

   NA

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7. Learned Indian classical vocalists do not like the accompaniment of a harmonium because

1. 1. Tempered scale is used in the harmonium

   
   
   

   2. Diatonic scale is used in the harmonium

   
   
   

   3. Notes of the harmonium are too shrill

   
   
   

   4. Intensity of the notes of the harmonium is too large

   
   
   

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   NA

   Correct Option: A

   NA

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8. Assertion (A) : Radio waves bend in a magnetic field
   Reason (R) : Radio waves are electromagnetic in nature
   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 not the correct explanation of A

   
   
   

   3. A is true, but R is false

   
   
   

   4. A is false, but R is true

   
   
   

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   NA

   Correct Option: D

   NA

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9. The speed of sound in air at S.T.P. is 300 m / s. If the air pressure becomes double, the temperature remaining the same, the speed of sound would

1. 1. 1200 m / s

   
   
   

   2. 600 m / s

   
   
   

   3. 300 m / s

   
   
   

   4. 300 √2 m / s
      

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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10. Ultrasonic waves are used for stirring liquid solutions because they

1. 1. Do not produce noise during the operation

   
   
   

   2. Are easy to produce

   
   
   

   3. Can produce perfectly homogeneous solution

   
   
   

   4. Do not produce chemical reactions in the solution

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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