WAVES: There are three types of waves:
- Mechanical waves require a material medium to travel (air, water, ropes). These waves are divided into three different types.
- Transverse waves cause the medium to move perpendicular to the direction of the wave.
- Longitudinal waves cause the medium to move parallel to the direction of the wave.
- Surface waves are both transverse waves and longitudinal waves mixed in one medium.
- Electromagnetic waves do not require a medium to travel (light, radio).
- Matter waves are produced by electrons and particles.
- A point of maximum positive displacement in a wave, is called crest, and a point of maximum negative displacement is called trough.
- Measuring Waves: Any point on a transverse wave moves up and down in a repeating pattern. The shortest time that a point takes to return to the initial position (one vibration) is called period, T.
- The number of vibrations per second is called frequency and is measured in hertz (Hz). Here's the equation for frequency: f = 1 / T
- The shortest distance between peaks, the highest points, and troughs, the lowest points, is the wavelength, λ.
- By knowing the frequency of a wave and its wavelength, we can find its speed. Here is the equation for the velocity of a wave: v= λf.
- However, the velocity of a wave is only affected by the properties of the medium. It is not possible to increase the speed of a wave by increasing its wavelength. By doing this, the number of vibrations per second decreases and therefore the velocity remains the same.
- The amplitude of a wave is the distance from a crest to where the wave is at equilibrium. The amplitude is used to measure the energy transferred by the wave. The bigger the distance, the greater the energy transferred.
RETURN TO:
0 comments:
Post a Comment