1.5- Features of Waves

1.5- Features of Waves

1. Transverse and Longitudinal waves

   • There are two types of waves: transverse and longitudinal. Transverse waves are when the direction of motion of the water is at right angles to the direction of vibration of the wave. Longitudinal waves are when the direction of motion is the same as the direction of vibration of the wave. Transverse waves travel as a series of peaks and troughs, whilst longitudinal wave travel as compressions and rarefactions.

2. How do we describe waves?

   • Waves at described in terms of their wavelength, frequency, speed and amplitude. The wavelength of a wave is the distance that the wave takes to repeat itself- this is normally measured from one crest to the next crest. Wavelength is measured in metres, m.
     • Frequency of a waves is the number of waves that pass a point in 1 second. Frequency is measured in hertz, Hz, where 1Hz= 1 wave per second.
     • The speed of a wave, v, is the distance that a wave travels in 1 second. Wave speed is measured in metres per second, m/s.
     • The amplitude of a wave is a measure of the energy carried by the wave. Amplitude is measured from the undisturbed (normal) position, to the top of a crest or the bottom of a trough. Loud sounds have larger amplitudes than quiet sounds.

3. Calculating wave speed, frequency and wavelength

   • Wave speed can be calculated using the equation:
     • wave speed= distance/ time
   • Frequency or wavelength can be calculated using the equation:
     • wave speed= frequency x wavelength

4. Waves travel at a range of different speeds. All electromagnetic waves travel at the speed of light: 3x108 m/s

5. Electromagnetic Spectrum

   • arts of the electromagnetic spectrum have different wavelengths and frequencies and energies.