VIBRATIONS AND WAVES

• Vibration is a periodic wiggle in time.
• Wave is a periodic wiggle in both space and time, propagating in a medium or in a vacuum, carrying energy with them.
• Waves are classified by what they move through (Medium) and how particles move through them.
• Electromagnetic Waves are waves that can travel through matter or empty space where matter is not present.
• Rarefactional waves are waves that spread out an area causing a low-pressure region.
• Compressional waves are waves that have a reduced area causing a high-pressure region.
• Types of Electromagnetic Waves include radio waves, microwaves, infrared waves, visible light, ultraviolet rays, X-rays, and Gamma rays.
• Mechanical Waves need a medium to travel, requiring the particles of the medium to vibrate in order for energy to be transferred.
• The bending of a wave increases with a greater change in speed.
• The period of a pendulum depends on the length of the pendulum and is independent of the mass of the pendulum.
• The restoring force acts in a direction opposite that of the displacement.
• When two or more waves combine together, they can create a larger wave (crescendo & crescendo) or destroy the wave completely.
• Reflection does not change the speed or frequency of the wave, but the wave can be flipped upside down.
• The bending of a wave as it enters a new medium is caused by a change in the speed of the wave as it moves from one medium to another.
• When a wave curves around an obstacle or passes through a narrow opening, it will curve around trying to reach the boundary or outward through the opening due to friction.
• When a wave meets a hard surface, it bounces back.
• Types of Mechanical Waves include water waves, earthquake/seismic sound waves, and waves that travel down a rope or spring.
• Transverse Waves are waves where particles move perpendicular to the motion of the wave.
• Resonance occurs when one object vibrates without touching another, causing the two objects to resonate at the same frequency with amplitude increasing over time.
• Polarization filtering, radiating, and lighting (moves in all directions) to allow only light traveling in one direction through.
• Doppler Effect is the change in frequency due to the motion of the source (or receiver).
• Bow Waves are a V-shaped wave pattern produced by the source once it moves faster than the wave speed.
• Shock Waves are a cone-shaped disturbance created by an object moving at supersonic speed through the fluid, resulting in a sonic boom.
• Longitudinal Waves are waves where particles move parallel to the motion of the wave.
• Wavelength (λ) is the distance from crest to crest (or through to through), expressed in meters.
• Amplitude (A) is the distance of crest (or through) from the midpoint of the wave.