Answer
$20\;W$
Work Step by Step
In the previous section of this problem, we have calculated that the average rate at which energy is transported by the wave to the opposite end of the cord is $10\;W$.
If, simultaneously, an identical wave travels along an adjacent, identical cord, the average rate at which energy is transported by the wave in the new cord will also be $10\;W$.
Therefore, the total average rate at which energy is transported to the opposite ends of the two cords by the waves is $(10+10)\;W=20\;W$.
