Wave Interactions Chapter 11.3 Science Spectrum

Reflection Reflection is simply the bouncing back of a wave as it meets a surface or boundary. Reflection is simply the bouncing back of a wave as it meets a surface or boundary. Examples: Echoes and light Examples: Echoes and light

Diffraction Diffraction is the bending of a wave as it passes an edge or an opening. Diffraction is the bending of a wave as it passes an edge or an opening. Example: When water waves goes through an opening or passing through an obstacle. Example: When water waves goes through an opening or passing through an obstacle. /Diffraction2.htm /Diffraction2.htm /Diffraction2.htm /Diffraction2.htm

Refraction Refraction is the bending of waves as they pass from one medium to another. Refraction is the bending of waves as they pass from one medium to another. Example: An object appears bent when part of it is submerged in water. Example: An object appears bent when part of it is submerged in water.

Interference The combination of two or more waves that exist in the same place at the same time. The combination of two or more waves that exist in the same place at the same time. There are two types of interference. There are two types of interference. Constructive Interference Constructive Interference Destructive Interference Destructive Interference

Constructive Interference Any interference in which waves combine so that the resulting wave is bigger than the original waves. Any interference in which waves combine so that the resulting wave is bigger than the original waves.

Two Crest adds up to one large crest Constructive Interference Two Troughs adds up to one large trough

Destructive Interference Any interference in which waves combine so that the resulting wave is smaller than the largest of the original waves. Any interference in which waves combine so that the resulting wave is smaller than the largest of the original waves.

Destructive Interference A crest and a trough cancels each other out.

After Interference After constructive or destructive interference, the waves will resume its normal form.

Practice Problem #1 Determine whether the interference between the waves is constructive or destructive depending on the part of the wave. Determine whether the interference between the waves is constructive or destructive depending on the part of the wave.

Answer to #1 Constructive Interference Constructive Interference G, J, M, N Destructive Interference Destructive Interference H, I, K, L, O

Practice Problem #2 Twin water bugs Jimminy and Johnny are both creating a series of circular waves by jiggling their legs in the water. The waves undergo interference and create the pattern represented in the diagram at the top. The thick lines in the diagram represent wave crests and the thin lines represent wave troughs. Several of positions in the water are labeled with a letter. Categorize each labeled position as being a position where either constructive or destructive interference occurs. Twin water bugs Jimminy and Johnny are both creating a series of circular waves by jiggling their legs in the water. The waves undergo interference and create the pattern represented in the diagram at the top. The thick lines in the diagram represent wave crests and the thin lines represent wave troughs. Several of positions in the water are labeled with a letter. Categorize each labeled position as being a position where either constructive or destructive interference occurs.

Practice Problem #2 Thin lines = troughThick lines = crest

Answer to #2 Constructive Interference Constructive Interference A & B Destructive Interference Destructive Interference C, D, E, & F