Unit 12: Waves

Learning Objectives:

PSc.3.2.1

• Identify the basic characteristics of a longitudinal (compressional) wave: amplitude, rarefaction, and compression.

• Recognize the relationship between period and frequency (focus on conceptual understanding of this inverse relationship).

• Explain the relationship among velocity, frequency, and wavelength and use it to solve wave problems: v_w = f λ

• Exemplify wave energy as related to its amplitude and independent of velocity, frequency or wavelength.

PSc.3.2.2

• Classify waves as one of three types: mechanical, electromagnetic or surface waves based on their characteristics.

• Compare different wave types based on how they are produced, wave speed, type of material (medium) required, and motion of particles.

PSc.3.2.3

• Compare compressional (longitudinal) and transverse waves in terms of particle motion relative to wave direction.

PSc.3.2.4

• Illustrate reflection and refraction of waves at boundaries: reflection of a transverse pulse at the fixed-end of a spring or rope; reflection of sound (SONAR) and radio waves (RADAR); reflection of water (surface) waves; refraction of water waves as the depth of the water changes; sound as it changes media; refraction of light as it passes from air into water, glass, oil etc.

• Illustrate the effects of wave interference (superposition)–constructive and destructive interference of surface waves, mechanical waves (sound, pulses in springs/ropes, etc.), light (soap bubbles/thin films, diffraction gratings). Emphasis is on conceptual understanding – not mathematical relationships.