Line graph titled “Speed of Sound in Water at Different Temperatures.” The graph shows water temperature on the x-axis, measured in degrees Celsius, and the speed of sound on the y-axis, measured in meters per second (m/s). As water temperature increases from 0°C to 40°C, the speed of sound increases steadily from about 1400 m/s to about 1530 m/s. The graph shows an upward trend, indicating that sound travels faster in warmer water.

Sound travels when particles vibrate and pass energy from one particle to the next. How fast sound travels depends on how quickly vibrations are transferred, not just how close particles are.

 

In different states of matter:

  • In gases, particles are far apart, so vibrations are passed slowly

  • In liquids, particles are closer together, so vibrations move faster

  • In solids, particles are tightly packed and strongly connected, allowing vibrations to move fastest

Within liquid water, temperature changes affect particle motion in a different way. As water gets warmer, particles move faster and transfer vibrations more quickly, even though they may be slightly farther apart. The increased motion helps sound waves move through the water more efficiently.

This graph shows how particle motion in liquid water affects the speed of sound as temperature increases.

How does the speed of sound in liquid water change as temperature increases?

 

Claim
Make a claim describing how the speed of sound in water changes as temperature increases.

 

Evidence
Use specific values from the graph to support your claim. Include at least two temperatures and the corresponding speeds of sound (m/s).

 

Reasoning
Explain why this pattern occurs. In your explanation, describe how particle motion changes as temperature increases this affects the speed of sound.

  1. About how fast does sound travel in water at 0°C, and how does this compare to the speed at 40°C?

  2. What overall pattern do you notice in the graph as temperature increases?

  3. Between which two temperature measurements shown does the speed of sound increase the most?

  4. How might this change in sound speed affect animals that rely on sound in water, such as whales or dolphins?

  5. Why do you think scientists study sound speed in water at different temperatures instead of just one temperature?