How Elasticity Affects the Speed of Waves

Gas Medium

• Sound waves move through a medium by transferring kinetic energy from one molecule to the next molecule. In particular, gas naturally has large spaces between each molecule. As a result, sound waves take longer to move through a gas. Each air molecule vibrates at a slow speed after a sound wave passes through it since there is more space surrounding the molecule. The gas molecule effectively deforms in shape from the passing sound wave, making gas reflect a low elasticity. In fact, sound waves moving through an air temperature of 68 degrees Fahrenheit will only travel approximately 767 miles per hour.

Liquid Medium

• Liquid molecules bond together in a tighter formation, compared to gas molecules. The liquid molecules are more limited in their overall spacing, allowing only small vibration movements. As a result, sound waves do not deform the liquid molecules as severely as gas molecules, creating a higher elasticity level. Sound waves moving through water at 70 degrees Fahrenheit travel at approximately 3,321 miles per hour.

Solid Medium

• Solid mediums, such as aluminum, transmit sound waves extremely fast. The solid molecules are tightly packed together, providing only tiny spaces for vibration. As a result, sound waves move rapidly through the high elasticity medium, since the solid molecules act like small springs, aiding the wave's movement across the medium. In fact, the speed of sound through aluminum is approximately 14,137 miles per hour.

Temperature and Elasticity

• Warmer temperatures across a medium excite molecules. As a result, molecules move faster under high temperatures, transmitting sound waves more rapidly across the medium. However, decreasing temperatures cause the molecules to vibrate at a slower pace, hindering the sound wave's movement.