When waves travel from one medium to another the frequency never changes. As waves travel into the denser medium, they slow down and wavelength decreases. Part of the wave travels faster for longer causing the wave to turn. The wave is slower but the wavelength is shorter meaning frequency remains the same.

(1) Rarer and denser medium : A medium is said to be denser (relative to the other) if the speed of wave in this medium is less than the speed of the wave in other medium. In comparison to air speed of sound is maximum in water, hence water is rarer medium for sound waves w.r.t. air.

Sound waves need particles to propagate. They move forward by vibrating particles in medium. So if it is a denser medium sound energy can vibrate more particles in less time since in denser mediums molecules are packed tight. Hence in absence of medium sound cannot travel because no particles exist.

Sound is a mechanical wave and travels by compression and rarefaction of the medium. A higher density leads to more elasticity in the medium and hence the ease by which compression and rarefaction can take place. This way the velocity of sound increases by increase in density.

Waves and Energy: Waves travel through a medium: A medium is any substance or region through which a wave is transmitted. The speed of a wave is dependant on four factors: wavelength, frequency, medium, and temperature. This is due to the increased kinetic energy of the air molecules and the decrease in density.

Examples of optically denser medium are when we are comparing two medium air and water, air is the rare medium and water is the denser medium. Examples of optically denser medium are when we are comparing two medium air and water, air is the rare medium and water is the denser medium.

The medium with greater refractive index is called the denser medium and the one with smaller refractive index is called the rarer medium. The speed of wave is less in denser medium than that in a rarer medium.

The medium with greater refractive index is called the denser medium and the one with smaller refractive index is called the rarer medium. When wave travels from denser to rarer medium it bends away from the normal and angle of refraction is greater than angle of incident.

ï More dense to a less dense medium, the light wave speeds up and bends away from the normal. ï Less dense to a more dense medium the light wave slows down and bends toward the normal. The greater the angle of incidence the larger the angle of refraction.

Sound travels at different speeds depending on what it is traveling through. Of the three mediums (gas, liquid, and solid) sound waves travel the slowest through gases, faster through liquids, and fastest through solids. Temperature also affects the speed of sound.

Waves always travel fastest in the least dense medium. Thus, the reflected pulse will be traveling faster than the transmitted pulse. Second, particles in the more dense medium will be vibrating with the same frequency as particles in the less dense medium.

A higher density leads to more elasticity in the medium and hence the ease by which compression and rarefaction can take place. This way the velocity of sound increases by increase in density. Light on the other hand is a transverse electromagnetic wave.

You see, these two are different types of energy waves. Sound waves and ocean waves are mechanical ones. Therefore, they need a medium to travel. Ocean waves are caused by energy shifting the water, while sound waves can travel through many mediums, including air and water.

The properties of a sound wave change when it travels through different media: gas (e.g. air), liquid (e.g. water) or solid (e.g. bone). When a wave passes through a denser medium, it goes faster than it does through a less-dense medium.

What the sound wave will sound like when it reaches the ear depends on a number of things such as the medium it travels through and the strength of the initial vibration.