6. What is the difference between Bluetooth and WI-Fi devices ?

1. 1. Bluetooth used 2.4 GHz radio frequency band whereas Wi-Fi can use 2.4 CHz or 5 GHz frequency band

   
   
   

   2. Bluetooth is used for wireless local area networks (WLAN) only whereas Wi-Fi is used for wireless wide area networks (WWAN) only

   
   
   

   3. When information is transmitted between two devices using bluetooth technology, the devices have to be in the line of sight of each other, but when Wi-Fi technology is used the devices need not be in the line of sight of each other

   
   
   

   4. The statements (a) and (b) given above are correct in this context

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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7. A digital signal

1. 1. Is less reliable than analog signal

   
   
   

   2. Is more reliable than analog signal

   
   
   

   3. Is equally reliable as the analog signal

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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8. Modern communication systems use

1. 1. Analog circuits

   
   
   

   2. Digital circuits

   
   
   

   3. Combination of analog and digital circuits

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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9. Which of the following shows particle nature of hight ?

1. 1. Polarization

   
   
   

   2. Photoelectric effect

   
   
   

   3. Refraction

   
   
   

   4. Interference

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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10. In a transistor

1. 1. Both the emitter and the collector are equally doped

   
   
   

   2. Emitter is more heavily doped than the collector

   
   
   

   3. The base is made very thin and is lightly doped

   
   
   

   4. Both (b) and (c)

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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