If a coaxial cable has 7 dB of reflected power when the input is 5 watts, what is the output of the transmission line?

To find the output of the transmission line when there is reflected power, you start with the input power and take into account the reflected power loss expressed in decibels (dB). In this case, the input power is 5 watts, and you have 7 dB of reflected power.

First, you need to convert the reflected power from dB to a linear scale. A 7 dB reflection means that the power reflected back is a certain fraction of the input power. The formula to convert dB (decibels) to a linear gain (or loss) is:

[ \text{Power Ratio} = 10^{(dB/10)} ]

Thus, for a 7 dB reflection:

[ \text{Power Ratio} = 10^{(7/10)} \approx 5.012 ]

This means that the reflected power is approximately 5.012 times the power level in watts that it is being referenced against. However, because this is a reflection, the actual output power is the input power minus the reflected power.

To find the actual power being used by the load (the output power), you need to calculate how much power does not reflect. Since we initially had 5