To understand what happens to the speed of a sound wave as it travels from air into glass, you need to compare the speeds of sound in both mediums. Looking at the provided table:
[tex]\[
\begin{array}{|c|c|c|c|c|}
\hline
& \text{Water} & \text{Diamond} & \text{Glass} & \text{Air} \\
\hline
\begin{array}{c}
\text{Speed of} \\
\text{sound} \\
(\text{m/s})
\end{array} & 1,493 & 12,000 & 5,640 & 346 \\
\hline
\end{array}
\][/tex]
- The speed of sound in air is 346 m/s.
- The speed of sound in glass is 5640 m/s.
From this data, you can see that the speed of sound in glass (5640 m/s) is significantly greater than the speed of sound in air (346 m/s). Therefore, when a sound wave travels from air into glass, it is moving into a medium where the sound travels much faster.
Given the options:
A. It decreases.
B. It falls to zero.
C. It stays the same.
D. It increases.
The correct answer is D. It increases.
Thus, when a sound wave travels from air into glass, the speed of the sound wave increases.