Wave Characteristics

Student Expectation

The student is expected to examine and describe oscillatory motion and wave propagation in various types of media. They are also expected to investigate and analyze characteristics of waves, including velocity, frequency, amplitude, and wavelength, and calculate using the relationship between wavespeed, frequency, and wavelength.

Key Concepts

• • Oscillatory motion is back and forth motion about an equilibrium point. The force always acts in a direction opposite to the displacement of the moving object from the equilibrium point. Pendulums, swings, metronomes and speakers are examples of oscillatory motion.

  • Waves are oscillatory disturbances that travel through time and space.

  • The property of the medium through which the wave propagates affects the speed of the wave. The speed of a wave is determined by the properties of a particular medium at a given temperature.

  • Wavelength is defined as the distance between two adjacent crests of a wave. Frequency is defined as the number of crests passing a particular point per unit time. Wavelength and frequency are inversely proportional to each other.

  • The speed of a wave is equal to the product of its wavelength and frequency. The velocity of a wave can be analyzed by knowing its speed and its direction of propagation.

  • Amplitude is defined as the distance between the undisturbed line and the crest of a wave. A wave’s amplitude does not affect its speed or frequency.

  • Waves transfer net energy, they do not transfer net matter.

WAVES

WAVE PROPAGATION

One of the favorite places for vacations is Miami Beach, since people go there to appreciate beautiful waves from the Atlantic Ocean. Waves are oscillatory disturbances that travel through time and space. Waves are a common motion in nature.

Did you know that the Earth releases energy through waves? An earthquake is a natural disaster caused by waves. The property of the medium through which the wave travels affects the speed of the wave. The speed of a wave in a particular medium at a given temperature is defined and can be precisely measured.

WAVE CHARACTERISTICS

Waves travel through the earth from inside to outside, or through the mantle, the upper mantle, and the crust. These different structures possess different geological properties and various temperatures, and thus the speed of waves in these mediums will be different.

During an earthquake, waves spread in the Earth. In order to distribute waves and transfer energy, the medium must be elastic with a low frictional resistance so it does not dampen quickly.

If the medium is not elastic, the energy may be absorbed by the medium. To build a house that is anti-earthquake, one of the ways is to firmly tighten the ground. This is to reduce the elastic coefficient for protection.

The amplitude of a wave is related to the energy the wave takes. The bigger the amplitude is, the higher the energy it brings. Waves are a form of energy transportation. Waves transfer energy, but they do not transfer matter.

FORMULA FOR SPEED OF A WAVE

The speed of a wave is equal to the product of its wavelength and frequency.

Formula for speed of a wave

The velocity of a wave can be analyzed by knowing its speed and its direction of propagation. Velocity is a vector, and it has both magnitude and direction. A waves amplitude does not affect its speed or frequency.