Wave Interactions

Reflection – Bounce back wave Sound waves that are reflected are called echoes Used in sonar and echolocation How wave is reflected depends on if the end if “fixed” or free Opposite wave reflected Same side wave

Refraction The bending of a wave due to the wave moving from one type of medium into another. Caused by change in wave speed through the new medium

Diffraction Wave passing a barrier or going through a hole in a barrier bends causes the wave to wrap around the barrier ex) Hearing music playing but not knowing where it’s coming from or hearing sounds under water

Interference When two or more waves meet, they interact. This is called interference. 1. Constructive Interference – the combining of waves to cause higher amplitude of any of the original waves. 2. Destructive Interference – when the combining of the waves produce a new wave with a smaller amplitude than the beginning waves

Constructive Interference Waves with same amplitude meet Adds together to make a greater amplitude

Destructive Interference Waves with opposite amplitudes meet Waves meet and create smaller waves Wave keep moving along medium

Standing Waves Standing Waves – the combining of the incoming and reflected wave so that the resultant wave appears to be standing still Node – the point where Constructive Interference and Destructive Interference cause an amplitude of zero on the standing wave (no motion).