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A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz. The frequencies of the resultant signal is/are: (1) 2 MHz only (2) 2005 kHz, and 1995 kHz (3) 2005 kHz, 2000 kHz and 1995 kHz (4) 2000 kHz, and 1995 kHz

1. 2 MHz only
2. 2005 kHz, and 1995 kHz
3. 2005 kHz, 2000 kHz and 1995 kHz
4. 2000 kHz, and 1995 kHz

Correct answer: 2005 kHz, 2000 kHz and 1995 kHz

Solution

The correct option includes the carrier frequency (2 MHz or 2000 kHz) and the sidebands created by the modulation process, which are 5 kHz above and below the carrier frequency, resulting in frequencies of 2005 kHz and 1995 kHz.

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