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The total power content of an AM wave is...

The total power content of an AM wave is `2.64` KW at a modulation factor of `80%`. The power content of each side band is

A

160 w

B

320 w

C

480 w

D

640 w

Text Solution

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The correct Answer is:
To find the power content of each sideband in an amplitude modulated (AM) wave, we can follow these steps: ### Step 1: Understand the given data - Total power content of the AM wave, \( P_T = 2.64 \, \text{kW} = 2640 \, \text{W} \) - Modulation factor, \( M = 80\% = 0.8 \) ### Step 2: Calculate the power content of the carrier wave The power content of the carrier wave \( P_C \) can be calculated using the formula: \[ P_C = \frac{P_T}{2 + M^2} \] Substituting the values: \[ P_C = \frac{2640}{2 + (0.8)^2} \] Calculating \( (0.8)^2 \): \[ (0.8)^2 = 0.64 \] Now substituting back into the equation: \[ P_C = \frac{2640}{2 + 0.64} = \frac{2640}{2.64} \] Calculating \( P_C \): \[ P_C = 1000 \, \text{W} \] ### Step 3: Calculate the power content of each sideband The power content of each sideband (upper sideband \( P_{USB} \) and lower sideband \( P_{LSB} \)) can be calculated using the formula: \[ P_{USB} = P_{LSB} = \frac{M^2}{4} P_C \] Substituting the values: \[ P_{USB} = P_{LSB} = \frac{(0.8)^2}{4} \times 1000 \] Calculating \( \frac{(0.8)^2}{4} \): \[ P_{USB} = P_{LSB} = \frac{0.64}{4} \times 1000 = 0.16 \times 1000 = 160 \, \text{W} \] ### Final Answer The power content of each sideband is \( 160 \, \text{W} \). ---
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