Answer
$\sqrt{5.0}$ $\approx$ 2.2
Work Step by Step
If the wave speed, the medium density, and the frequency of the two waves are the same, then the intensity is proportional to the square of the amplitude. This is evident from equation 11–18.
Let “1” be the less energetic wave, and “2” be the more energetic wave.
$$\frac{I_2}{I_1}=5.0 = \frac{A_2^2}{A_1^2}$$
$$\frac{A_2}{A_1}=\sqrt{5.0}\approx 2.2$$
As expected, the wave with the larger amplitude carries more energy.