The attenuation of a signal is -10 dB. What is the final signal power if it was originally
5 W?

The final signal power if it was originally 5W is; 0.5 W

We are given;

Formula for attenuation signal is;

dB = 10log_10_ (P2/P1)

Where P2 is final signal power

Thus;

-10 = 10log_10_(P2/5)

-10/-10 = log_10_(P2/5)

-1 = log_10_(P2/5)

0.1 = P2/5

P2 = 0.1 × 5

P2 = 0.5 W

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P₂ = 0.5 W

Explanation:

It is given that,

The attenuation of a signal is -10 dB.

We need to find the final signal power if it was originally  5 W.

Using attenuation for signal :

Put dB = -10, P₁ = 5 W

Put all the values,

So, the final signal power is 0.5 W.