1 / 23

EDEXCEL IGCSE / CERTIFICATE IN PHYSICS 3-1 Properties of Waves

EDEXCEL IGCSE / CERTIFICATE IN PHYSICS 3-1 Properties of Waves. Content applying to Triple Science only is shown in red type on the next slide and is indicated on subsequent slides by ‘ TRIPLE ONLY ’. Edexcel IGCSE Physics pages 91 to 98. June 17 th 2012. Section 3: Waves

nolen
Download Presentation

EDEXCEL IGCSE / CERTIFICATE IN PHYSICS 3-1 Properties of Waves

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. EDEXCEL IGCSE / CERTIFICATE IN PHYSICS 3-1Properties of Waves Content applying to Triple Science only is shown in red type on the next slide and is indicated on subsequent slides by ‘TRIPLE ONLY’ Edexcel IGCSE Physics pages 91 to 98 June 17th 2012

  2. Section 3: Waves b) Properties of Waves understand the difference between longitudinal and transverse waves and describe experiments to show longitudinal and transverse waves in, for example, ropes, springs and water define amplitude, frequency, wavelength and period of a wave understand that waves transfer energy and information without transferring matter know and use the relationship: wave speed = frequency × wavelength v = f × λ use the relationship: frequency = 1 / time period f = 1 / T use the above relationships in different contexts including sound waves and electromagnetic waves understand that waves can be diffracted when they pass an edge understand that waves can be diffracted through gaps, and that the extent of diffraction depends on the wavelength and the physical dimension of the gap. Edexcel Specification Red type: Triple Science Only

  3. Waves A wave is a means of transferring energy and information from one point to another without there being any transfer of matter between the two points.

  4. vibrations wave direction TRANSVERSE WAVE Transverse Waves Transverse waves are waves where the direction of vibrations is at 90° to the direction in which the wave travels. example: water waves

  5. vibrations wave direction LONGITUDINAL WAVE longitudinal wave in slinky Longitudinal Waves Longitudinal waves are waves where the vibrations of the particles are along the direction in which the wave travels. example: sound waves

  6. Describing Waves1. Amplitude (A) Amplitude is the maximum movement of the particles that make up a wave from their rest position. amplitude rest position amplitude The amplitude is the height of a crest OR the depth of a trough

  7. 2. Wavelength (λ) Wavelength is the distance between one wave peak and the next wave peak along the path of a wave. Wavelength is measured in metres. wavelength wavelength Wavelength is also the distance between the bottom of one trough to the next.

  8. 3. Frequency (f ) Frequency is the number of wave peaks that pass a point in one second. Frequency is measured in hertz (Hz) 1 Hz = 1 peak per second 2 Hz = 2 peaks per second and so on…. 1 kilohertz (1kHz) = 1 000 Hz 1 megahertz (1MHz) = 1 000 000 Hz 1 gigahertz (1GHz) = 1 000 000 000 Hz 1 terahertz (1THz) = 1 000 000 000 000 Hz

  9. 4. Time period (T ) Time period is the time taken for a source to produce one wave. time period = 1 frequency and: frequency = 1 time period T = 1 / f f = 1 / T

  10. Question 1 Calculate the frequency of a wave of time period 8.0 seconds. f = 1 / T = 1 / 8 frequency = 0.125 hertz

  11. Question 2 Calculate the time period of a wave of frequency 50Hz. T = 1 / f = 1 / 50 time period = 0.020 second

  12. The wave equation speed = frequency x wavelength v=fxλ speed in metres per second (m/s) wavelength in metres (m) frequency in hertz (Hz) also:f=v÷λ and: λ=v÷f v f λ

  13. Question 1 Calculate the speed of a water wave of wavelength 3m and frequency 6Hz. v=fxλ = 6Hz x 3m speed = 18 m/s

  14. Question 2 Calculate the frequency of a wave in water of wavelength 2.0m if its speed is 16m/s. v=fxλ becomes: f=v÷λ = 16 m/s ÷ 2m frequency = 8 Hz

  15. Question 3 Calculate the wavelength of a sound wave in water of frequency 300Hz if its speed is 1500m/s. v=fxλ becomes: λ=v÷f = 1500 m/s ÷ 300 Hz wavelength = 5 metres

  16. Question 4 Calculate the speed of a wave that has a wavelength of 30m and time period 0.04s. f = 1 / T = 1 / 0.04s f= 25 hertz v=fxλ = 25Hz x 30m speed = 750 m/s

  17. Complete: Answers 60 m/s 165 Hz 200 000 Hz 3 m

  18. TRIPLE ONLY Sea wave diffraction Diffraction Diffraction occurs when waves spread out after passing through a gap or round an obstacle.

  19. TRIPLE ONLY Diffraction becomes more significant when the size of the gap or obstacle is reduced compared with the wavelength of the wave.

  20. Choose appropriate words to fill in the gaps below: A wave transfers _______ without the movement of _______ from one place to another. In a __________ wave the particle ____________ are perpendicular to the direction of wave travel. Frequency is equal to the number of waves produced by a source in one _________. Time period is equal to the ___________ of the frequency. The speed of a wave in m/s is equal to its __________ in metres multiplied by its __________ in hertz. energy matter transverse vibrations second reciprocal wavelength frequency WORD SELECTION: frequency transverse reciprocal energy second vibrations wavelength matter

  21. Simple demonstration of longitudinal & transverse waves - Freezeway.com Wave lab - shows simple transverse & longitudinal waves with reflection causing a stationary wave - by eChalk Wave Effects - PhET - Make waves with a dripping faucet, audio speaker, or laser! Add a second source or a pair of slits to create an interference pattern. Also shows diffraction. Virtual Ripple Tank - falstad Fifty-Fifty Game on Wave Types - by KT - Microsoft WORD Simple transverse wave - netfirms Simple longitudinal wave - netfirms Simple wave comparision - amplitude, wavelength - 7stones Fifty-Fifty Game on Wave Types - by KT - Microsoft WORD Wave on a String - PhET - Watch a string vibrate in slow motion. Wiggle the end of the string and make waves, or adjust the frequency and amplitude of an oscillator. Adjust the damping and tension. The end can be fixed, loose, or open. Vend diagram quiz comparing light and sound waves - eChalk BBC AQA GCSE Bitesize Revision: What are waves Amplitude, wavelength and frequency Wave speed Online Simulations

  22. TRIPLE ONLY Properties of WavesNotes questions from pages 91 to 98 • (a) What is a wave? (b) Explain the difference between a transverse and longitudinal wave (see pages 91 and 92) • Define what is meant by (a) amplitude; (b) wavelength; (c) frequency and (d) time period. (see pages 92 and 93) • (a) State the wave equation. (b) Calculate the wavelength of a radio wave of frequency 10MHz, speed 300 000km/s.(see pages 93 and 94) • (a) What is wave diffraction? (b) Draw diagrams showing how diffraction is affected by the wavelength of a wave. (see page 97) • Answer the questions on page 98. • Verify that you can do all of the items listed in the end of chapter checklist on page 98.

  23. DOUBLE ONLY Properties of WavesNotes questions from pages 91 to 98 • (a) What is a wave? (b) Explain the difference between a transverse and longitudinal wave (see pages 91 and 92) • Define what is meant by (a) amplitude; (b) wavelength; (c) frequency and (d) time period. (see pages 92 and 93) • (a) State the wave equation. (b) Calculate the wavelength of a radio wave of frequency 10MHz, speed 300 000km/s. (see pages 93 and 94) • Answer questions 1, 3 and 4 on page 98

More Related