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C. Wave behaviour

Created
2024/06/24 03:17
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C.1.1 Simple harmonic oscillations and its conditions

Oscillation: periodic motions which center around an equilibrium position
Wave: transfer of energy without transfer of matter
Simple harmonic motion (SHM): motion in which the restoring force (acceleration) is directly proportional to the displacement of the body from its equilibrium point
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Period and amplitude are constant
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Period is independent of amplitude
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Sinusoidal (can be represented into sine or cosine graph)
C.1.1-1 2D diagrams and graphs that represents SHM in pendulum
Condition for simple harmonic motion:
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A restoring force is required for simple harmonic motion to occur
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Magnitude of restoring force is proportional to displacement and acts towards the equilibrium
F∝−x,F=−kx(k=springconstant)F ∝-x, F=-kx (k=spring constant)
C.1 Simple Harmonic Motion

C.2.1 Traveling waves, wave properties, transverse and longitudinal waves

Key Terms
Traveling waves
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continuous disturbance in a medium that travels in the direction of propagation
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Energy is transferred by waves, but matter is not transferred by waves
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Waves are generated by oscillating sources
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Oscillations can propagate through a medium or in vacuum, depending on the type of wave
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Direction of a wave is defined as the direction of the propagation of energy
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continuous waves → succession of individual oscillations, wave pulse → one oscillation
C.2.1-1 Graph showing the progression of travelling wave
Types of Waves (Transverse / Longitudinal)
Real life Examples
C.2 Wave Model

C.3.1 Wavefronts and rays, Amplitude and Intensity

Wave characteristics and definitions
Waves can be described in terms of the motion of a wavefront and/or in terms of rays.
Wavefronts: surface joining neighboring points where oscillations are in phase with each other
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Can be curves or straight lines
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Always perpendicular to the direction of wave propagation
C.3.1-1 Diagram of progressing wave with notations
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(distance between successive wavefronts) = (λ\lambda of the wave)
C.3.1-2 Graph of transverse wave with key-terms notated
Rays: path taken by the wave energy propagation
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Indicate the direction of wave propagation
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Are perpendicular to wavefronts
C.3 Wave Phenomena

C.4.1 The nature of standing waves

Standing waves result from the superposition of two opposite identical waves:
Standing waves are formed when the two waves interfere with:
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the same amplitude
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the same frequency
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traveling in opposite directions
In standing waves:
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the positions of the crests and troughs do not change
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energy is not transferred yet there is energy associated with it.
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Nodes: the points where the total displacement always remains zero
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Antinodes: the points where the displacement varies between a maximum in one direction and in the other direction
C.4.1-1 A standing wave - the pattern remains fixed

C.4.2 Boundary conditions

C.4 Standing Waves and Resonance

C.5.1 The Doppler Effect

The Doppler effect
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When a source of sound, such as the whistle of a train or the siren of an ambulance, moves away from an observer :
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When the observer and the source of wave are both stationary :
C.5.1-1 Diagram of doppler effect (stationary)
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When the source starts to move towards the observer, the wavelength of the waves is shortened
C.5.1-2 Diagram of doppler effect (moving source)
Redshift/Blueshift of EM Radiation
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In space the Doppler effect of light can be observed when spectra of distant stars and galaxies are observed, this is known as :
C.5.1-3 Diagram of redshift
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Redshift : The fractional increase in wavelength due to the source and observer receding from each other
C.5 Doppler Effect