Waves and Energy sound, light*,water seismic (earthquakes)

Draw a mind map for waves and energy

Describe the characteristics of the wave. Mexican Wave clip

Properties of Waves A wave is a transfer of energy from one point to another with out the transfer of material between the two points. and sound waves from a speaker

Main properties of waves Other terms Period (T) units seconds (s), frequency (f) units hertz (Hz) speed (v) units metre/second (m/s) Text Pages

Calculations Frequency = 1/period f = 1/T unit Hertz (Hz) Speed = wavelength x frequency v = f unit metre/second (m/s) Assume speed in air 340 m/s unless told other wise.

Transverse Waves water waves, light waves*, some seismic waves In groups role model the movement of particles in a transverse wave e.g. water wave Text Page 6 – 8, 27 Creating a transverse wave

Transverse Wave

Longitudinal Wave sound waves and some seismic waves In groups role model the movement of particles in a longitudinal wave e.g. sound wave Text Pages 9 – 10,27 compressionrarefaction Creating a longitudinal wave

Tuning Forks Task : Strike each tuning fork on the bench and comment on its sound (pitch, loudness and intensity) Perceptive and subjective qualities of sound. Pitch is how high or low a sound seems (lion low, bird high) The louder the sound the more energy the sound wave has. Intensity is also linked to how high and often a wave occurs. Text Page

Key word links amplitude frequency loudness Pitch period wavelength Intensity

Speed of Sound Material Speed of Sound estimate Space Vacuum No sound Rubber at 20 o C 60 m/s Air at 40 o C355 m/s Air at 20 o C343 m/s Water at 20 o C1500 m/s Glass4540 m/s Steel at 20 o C4800 m/s Aluminum5000 m/s Speeds of Sound Text book page 39

Speed of sound Explain why the speed of sound is not constant (the same) for all materials. Explain why speed of sound is not the same for all temperatures

Draw waves to represent the following sounds Soft low frequency sound Loud high frequency sound Short wavelength loud sound

Describe the two waves below

Sound from a Speaker Loud speaker simulation Components of a speaker

Sound intensity level and distance Sound waves spread out in all directions decreases intensity.

Complete Review Properties of Waves Draw wave diagrams where needed Show all working Remember to place units on calculations Explanations may be in point form.

Hearing Ears work in a similar way to speakers. Frequencies at which a range of animals can hear

Interaction of waves with boundaries Reflection Prove: angle of incidence = angle of reflection Use light boxes to prove this rule Task Assessment: Criteria F

Interaction of waves with boundaries Refraction Bending and change of speed of waves as they pass from one medium to another. Task Investigate light waves moving from air to plastic. Assessment criteria D and E

Interaction of waves with boundaries

How does Homer see the box?