3 - Progressive and Stationary waves

• The top of a transverse wave is called a Crest
• The bottom of a transverse wave is called a trough
• Wavelength: The distance between two adjacent points on a wave moving in phase.
• Frequency: The number of complete oscillations or cycles per second, measured in Hertz (Hz).
• Amplitude: The maximum displacement from the equilibrium position.
• Period: Time taken for a point on a wave to pass through an entire cycle.
• Progressive wave: A disturbance in a medium caused by an oscillation that transfers energy from one place to another.
• Progressive Amplitude: All points have the same amplitude in turn, think of the skipping rope analogy
• Stationary amplitude: each point has a different amplitude at each point, moving back and forth.
• Regions of Compression have increased pressure
• Regions of Rarefaction have decreased pressure
• Longitudinal waves can be shown on a slinky spring
• Phase is the stage of a particle's motion in it's cycle.
• Phase difference: Difference in the fraction of a cycle completed between 2 oscillating particles
• Stationary: Between nodes, all particles are in phase.
• Stationary: Particles in the adjascent node to node sections are in antiphase to it
• Open-close: Closed acts as a node, open acts as an anti-node.
• Open-close: Only odd harmonics work, the frequency has a wavelength 4 times the length of the string, since it's half of the first harmonic.
• The frequency of a wave is it's fundamental character; it cannot change.
• Polarization is the process of restricting the oscillations of transverse waves to one plane.
• Common uses of polarization: Polaroid cameras, TV aerials and sunglasses. Reduces glare
• How the intensity of the wave varies with the angle between the transmission axes of the two polarisers/polarising filters.

  
• In real life, the intensity of the unpolarized EM waves decreases after passing through a polarising filter.
• Polarizing has maximas at 0, 180 and 360 and minimas at 90 and 270