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If omegac and omegam are angular frequen...

If` omega_c` and `omega_m` are angular frequencies of carrier wave and modulating signal respectively, then Band width of amplitude modulated waves is equal to

A

`(omega_c+omega_m)/2`

B

`2omega_m`

C

`2omega_c`

D

`(omega_c-omega_m)/2`

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The correct Answer is:
To find the bandwidth of amplitude modulated waves given the angular frequencies of the carrier wave (ω_c) and the modulating signal (ω_m), we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Components**: - The carrier wave has an angular frequency denoted by ω_c. - The modulating signal has an angular frequency denoted by ω_m. 2. **Identify the Sidebands**: - In amplitude modulation, the modulated signal creates two sidebands: - The Upper Sideband (USB) frequency is given by: \[ \text{USB} = \omega_c + \omega_m \] - The Lower Sideband (LSB) frequency is given by: \[ \text{LSB} = \omega_c - \omega_m \] 3. **Calculate the Bandwidth**: - The bandwidth (BW) of the amplitude modulated signal is defined as the difference between the maximum frequency (USB) and the minimum frequency (LSB): \[ \text{Bandwidth} = \text{USB} - \text{LSB} \] - Substituting the expressions for USB and LSB: \[ \text{Bandwidth} = (\omega_c + \omega_m) - (\omega_c - \omega_m) \] 4. **Simplify the Expression**: - Simplifying the equation: \[ \text{Bandwidth} = \omega_c + \omega_m - \omega_c + \omega_m \] \[ \text{Bandwidth} = 2\omega_m \] 5. **Final Result**: - Therefore, the bandwidth of amplitude modulated waves is: \[ \text{Bandwidth} = 2\omega_m \] ### Conclusion: The bandwidth of amplitude modulated waves is equal to \( 2\omega_m \).
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