Wave properties

• Wave fronts are the points where the wave meets the surface of the water. (lines of constant phase)
• The direction at which a wave travels is at right angles to the wavefronts.
• Reflection occurs when a wave is reflected from a boundary between two different media. It bounces off the surface of the material.
• Refraction is when the wave speed changes as they pass through a medium that has a different density. This causes the waves to bend or refract.
• Diffraction occurs when waves spread out after passing through a gap. The narrower the gap, the more the waves will spread out after passing through. The longer the wavelength, the more the waves spread out.
• The principle of superposition states that when two waves meet, the total displacement at a point is equal to the sum of the individual displacements at that point.

  Superposition occurs when waves meet and combine for an instant before moving apart again.
• When a crest meets a crest, they reinforce each other. A supercrest is created. Their amplitudes will add together.
• When a trough and a trough meet, a super trough will be formed. The waves reinforce one another.
• When a crest and a trough meet, a node is created. The resultant displacement is zero as the waves cancel each other out. This is known as a minimum.
• A node is a point on a stationary wave where there is zero amplitude.
• An antinode is a point on a standing wave where the maximum amplitude can occur.
• Stationary waves are waves that oscillate at a fixed frequency and are not moving. They have no flow of energy. Amplitude is different for all particles.
• Progressive waves are longitudinal waves that travel in a straight line and are slower than transverse waves