1. Waves
(a) describe what is meant by wave motion as illustrated by vibration in ropes, springs and ripple tanks
(b) show an understanding of and use the terms displacement, amplitude, phase difference, period, frequency, wavelength and speed
(c) deduce, from the definitions of speed, frequency and wavelength, the equation v = fλ
(d) recall and use the equation v = fλ
(e) show an understanding that energy is transferred due to a progressive wave
(f) recall and use the relationship intensity ∝ (amplitude)2
(g) compare transverse and longitudinal waves
(h) analyse and interpret graphical representations of transverse and longitudinal waves

2. Describing waves Read p112-114 and p117 Define in your notes:
Displacement
Amplitude
phase difference
Period
Frequency
Wavelength
speed

3. Demonstration / Exploration
A wave is caused by a vibrating source, and travels outwards from the source.
The particles of the medium through which a wave travels move about their equilibrium positions; they do not move along with the wave.
Energy is transferred from place to place by a wave.
You can demonstrate these points by showing waves on a stretched spring.

4. The wave equation
v = fλ
In one complete cycle a wavefront has moved forward by 1 wavelength.
f is no of complete cycles in one second
No of waves (per second)x length of one wave
Is distance moved in one second = speed

5. Practise
P 123 q2-4
P160 q 1,2,4

6. Energy in waves
intensity ∝ (amplitude)2