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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

Define Modulation and Transducer

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प्रश्न

Define modulation and transducer

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उत्तर

Modulation:-

The process of superimposing a low frequency signal on a high frequency wave, which acts as a carrier wave for long distance transmission is known as modulation.

Transducer:-

A transducer is a device, which converts one form of energy into another.

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2014-2015 (October)

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संबंधित प्रश्‍न

The process of superimposing a low frequency signal on a high frequency wave is_______ .


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In the block diagram of a simple modulator for obtaining an AM signal, shown in the figure, identify the boxes A and B. Write their function.


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Answer the following question.
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A speech signal of 3 kHz is used to modulate a carrier signal of frequency 1 MHz, using amplitude modulation. The frequencies of the sidebands will be ______.


I-V characteristics of four devices are shown in Figures.

(i) (ii) (iii) (iv)

Identify devices that can be used for modulation.


An audio signal of 15kHz frequency cannot be transmitted over long distances without modulation because ______.

  1. the size of the required antenna would be at least 5 km which is not convenient.
  2. the audio signal can not be transmitted through sky waves.
  3. the size of the required antenna would be at least 20 km, which is not convenient.
  4. effective power transmitted would be very low, if the size of the antenna is less than 5 km.

A TV transmission tower antenna is at a height of 20 m. How much service area can it cover if the receiving antenna is (i) at ground level, (ii) at a height of 25 m? Calculate the percentage increase in area covered in case (ii) relative to case (i).


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