Fundamental Wave Properties to Know for AP Physics 2 (2025)

“Waves"

"Disturbances that move energy across space or a medium without moving matter."

"Mechanical Waves"

"Require a medium for propagation, such as solid, liquid, or gas. Examples include sound waves and seismic waves."

"Transverse Waves"

"Waves where the direction of propagation is perpendicular to the particle movement. Example: light waves."

"Longitudinal Waves"

"Waves where the direction of propagation is parallel to the particle movement. Example: sound waves."

"Electromagnetic Waves"

"Do not require a medium and can move through a vacuum. Examples include X-rays and radio waves."

"Matter Waves"

"Connected to particles, demonstrating wave-particle duality. Example: de Broglie waves."

"Wavelength (λ)"

"Distance between two successive points in phase, such as crest to crest. Measured in meters (m)."

"Frequency (f)"

"Number of waves passing a point per second. Measured in hertz (Hz)."

"Time Period (T)"

"Time for one complete wave cycle. T = 1/f. Measured in seconds (s)."

"Amplitude (A)"

"Maximum displacement from equilibrium, indicating wave intensity or energy."

"Wave Speed (v)"

"Speed of energy transmission, related to wavelength and frequency by v = f × λ. Measured in m/s."

"Reflection"

"When a wave bounces back upon hitting a surface. Angle of incidence equals angle of reflection."

"Refraction"

"Change in wave direction due to a speed change in different mediums. Described by Snell's Law."

"Diffraction"

"Bending of waves around obstacles or through openings, prominent when wavelength matches obstacle size."

"Interference"

"Combination of waves to form a resultant wave, leading to constructive or destructive interference."