2.6 what is a wave
- 1. What is a wave? 29 January 2015 How many types of wave have you heard of in everyday use? Do they have anything in common?
- 2. Aims • Describe the origin of a wave • Explain the properties of a wave
- 3. Key terms • Displacement: how far the wave is disturbed from its rest position • Oscillation: a complete to and fro movement; this could be going up and down or sideways
- 4. What is a wave? A wave is a disturbance moving through a material
- 5. What causes a wave? • The source of a wave is always something that vibrates • The material that the wave travels through is called the medium
- 10. Amplitude, A • The maximum distance that each point in the medium moves from its normal position as the wave passes • Measured in metres, m
- 11. Frequency, f • This is the number of waves that pass any point in the medium every second, so it is the same as the number of vibrations per second • Frequency is measured in per seconds or hertz, 1/s, s-1 or Hz
- 12. Wave speed, v • This is the speed at which each wave crest moves through the medium. • Measured in metres per second, m/s or ms-1
- 13. Wavelength, λ • This is the length of a complete wave measured from any point to the next identical point – the distance is always the same no matter which point you choose • It is measured in metres, m
- 14. Wavelength, λ • This is the length of a complete wave measured from any point to the next identical point – the distance is always the same no matter which point you choose • It is measured in metres, m
- 15. fv Where: v = speed of wave / m/s f = frequency of wave / Hz (1/s) λ = wavelength of wave / m
- 16. How can we prove this? 1 1 330 330 msf msv fv What would happen if we increased the wavelength of a wave? What would happen if we decreased the wavelength of a wave?
- 26. Assessment activity 2.6 • Discuss how you could model the movement of a wave (P3) • Construct your model or role play it to another group • REMEMBER: the longer the wavelength, the smaller the frequency. When calculating speed, make sure you change the prefixes