When a sound wave passes from air into water, several changes occur to its speed, frequency, and wavelength due to the difference in the medium's properties. Sound waves are mechanical waves that require a medium (like air, water, or solid) to travel through.
Speed: The speed of sound in a medium depends on its density and elasticity. Water is denser and more elastic than air, which means sound waves can travel faster in water than in air. On average, sound travels at about 343 meters per second (m/s) in air at room temperature, while in water, it travels at approximately 1484 m/s, almost four times faster.
Frequency: The frequency of a sound wave, measured in hertz (Hz), remains the same when it passes from one medium to another. Frequency is the number of oscillations (or cycles) per second, and it is determined by the source of the sound. So, when sound moves from air to water, the frequency of the wave remains constant.
Wavelength: The wavelength of a sound wave is related to its speed and frequency through the formula: wavelength = speed / frequency. Since the frequency remains constant and the speed increases when sound travels from air to water, the wavelength also changes. In water, where the speed of sound is higher, the wavelength will be shorter compared to its wavelength in air.
To summarize:
- Speed increases when sound moves from air to water.
- Frequency remains constant regardless of the medium.
- Wavelength becomes shorter in water compared to its wavelength in air.