waves_31_jan_2akakakakakkakakka024.pptx.pdf
- 1. Waves
- 2. Waves When a stone is dropped into a pond, ripples begin to spread out across the surface.
- 3. Waves The tiny waves carry energy – but there is no actual flow of water across the pond.
- 4. Waves Waves are just the up and down movement in water. Peak Trough
- 5. Waves Waves are just the up and down movement in water. Peak Trough There are other sorts of waves, such as: Sound Radio Light
- 6. Waves Waves are just the up and down movement in water. Peak Trough There are other sorts of waves, such as: Sound Radio Light Waves have features in common, and can be divided into two main types: 1. Transverse 2. Longitudinal
- 7. Transverse Waves Eg. light, ultra-violet, gamma rays, radio.
- 8. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. The to-and-fro movements of the wave are called oscillations. In a transverse wave these oscillations are at right angles to the direction in which the energy is travelling.
- 9. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. The to-and-fro movements of the wave are called oscillations. In a transverse wave these oscillations are at right angles to the direction in which the energy is travelling.
- 10. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. Features of transverse waves 1. Wavelength. The distance between any two corresponding points on the wave. (metres)
- 11. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. Features of transverse waves 1. Wavelength. The distance between any two corresponding points on the wave. (metres) 2. Amplitude. The maximum displacement of the wave from its rest point.
- 12. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. Features of transverse waves 1. Wavelength. The distance between any two corresponding points on the wave. (metres) 2. Amplitude. The maximum displacement of the wave from its rest point. 3. Speed. The speed of the wave is measured in metres per second (m/s).
- 13. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. Features of transverse waves 4. Frequency. The number of waves passing any point in one second. The unit of frequency is the hertz (Hz). One hertz is one vibration of the wave per second. The time for one oscillation is called the period.
- 14. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. Features of transverse waves 4. Frequency. The number of waves passing any point in one second. The unit of frequency is the hertz (Hz). One hertz is one vibration of the wave per second. The time for one oscillation is called the period. For example, if five complete waves pass a given point in one second (i.e. five complete oscillations) then the frequency is 5 Hz.
- 15. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. Features of transverse waves Remember! The frequency (in Hz) is the number of oscillations per second. The period (in seconds) is the time for one complete oscillation. Frequency = 1 period
- 16. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. The wave equation Linking together speed, frequency and wavelength.
- 17. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. The wave equation Linking together speed, frequency and wavelength. Speed = frequency x wavelength
- 18. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. The wave equation Linking together speed, frequency and wavelength. Speed = frequency x wavelength v = f λ (λ = Greek letter lambda)
- 19. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. The wave equation Linking together speed, frequency and wavelength. Speed = frequency x wavelength v = f λ (λ = Greek letter lambda) m/s Hz m
- 20. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. The wave equation Linking together speed, frequency and wavelength. Example 1: a wave has a wavelength of 12m. Calculate the wave speed if it has a frequency of 20 Hz. v = f λ
- 21. Transverse Waves Eg. light, ultra-violet, gamma rays, radio. The wave equation Linking together speed, frequency and wavelength. Example 1: a wave has a wavelength of 12m. Calculate the wave speed if it has a frequency of 20 Hz. v = f λ Example 2: a wave has a frequency of 10 Hz. Calculate the wavelength if it has a wave speed of 50 m/s. v = f λ λ = v / f