Stan W Zochowski Condensed Matter and Materials Physics

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Stan W. Zochowski Condensed Matter and Materials Physics Department of Physics and Astronomy University

Stan W. Zochowski Condensed Matter and Materials Physics Department of Physics and Astronomy University College London http: //www. cmmp. ucl. ac. uk/~swz/#IUL

Wave pulse Animation courtesy of Dr. Dan Russell, Kettering University

Wave pulse Animation courtesy of Dr. Dan Russell, Kettering University

Transverse Waves Animation courtesy of Dr. Dan Russell, Kettering University

Transverse Waves Animation courtesy of Dr. Dan Russell, Kettering University

Forces in a fragment of the tight rope

Forces in a fragment of the tight rope

Longitudinal Waves Animation courtesy of Dr. Dan Russell, Kettering University

Longitudinal Waves Animation courtesy of Dr. Dan Russell, Kettering University

Fala dźwiękowa czyli… rozchodzące się zagęszczenia i rozrzedzenia cząsteczek np. powietrza 6

Fala dźwiękowa czyli… rozchodzące się zagęszczenia i rozrzedzenia cząsteczek np. powietrza 6

Water Waves Animation courtesy of Dr. Dan Russell, Kettering University

Water Waves Animation courtesy of Dr. Dan Russell, Kettering University

Clockwise or anticlockwise? ? ?

Clockwise or anticlockwise? ? ?

Rayleigh surface waves Animation courtesy of Dr. Dan Russell, Kettering University

Rayleigh surface waves Animation courtesy of Dr. Dan Russell, Kettering University

Długość, amplituda i prędkość fali

Długość, amplituda i prędkość fali

Jest fala – jest drganie!

Jest fala – jest drganie!

Reflection from a HARD boundary Acoustics and Vibration Animations - Dan Russell, Kettering University

Reflection from a HARD boundary Acoustics and Vibration Animations - Dan Russell, Kettering University

Reflection from a SOFT boundary Acoustics and Vibration Animations - Dan Russell, Kettering University

Reflection from a SOFT boundary Acoustics and Vibration Animations - Dan Russell, Kettering University

Odbicie fal (sprężystych) 14

Odbicie fal (sprężystych) 14

As spherical wave expands, its radius increases and the wavefronts flatten. At very large

As spherical wave expands, its radius increases and the wavefronts flatten. At very large distances, the wavefronts are quite flat and the disturbance resembles a plane wave. The phase of the disturbance is the same at all points on a wavefront. A wavefront is a surface of constant phase.

Sound waves are acoustic waves, with no electrical component. They are simply vibrations in

Sound waves are acoustic waves, with no electrical component. They are simply vibrations in the air, a physical pressure. "Audible sound is thus defined as a disturbance in the atmosphere whereby a form of wave motion is propagated from some source at a velocity of 1, 075 feet per second, the transmission being accomplished by alternating condensations and rarefactions of the atmosphere in cycles having a fundamental frequency ranging somewhere between 16 per second and 32, 000 per second. "

Measurement of Sound Intensity: power per unit area, or, rate at which energy transported

Measurement of Sound Intensity: power per unit area, or, rate at which energy transported by the wave flows through a unit area A perpendicular to the direction of travel of the wave

DOPPLER EFFECT

DOPPLER EFFECT

Observer moving towards stationary source:

Observer moving towards stationary source:

Source moving towards stationary observer:

Source moving towards stationary observer:

Efekt Dopplera http: //www. ionaphysics. org/ntnujava/Doppler. html

Efekt Dopplera http: //www. ionaphysics. org/ntnujava/Doppler. html

Source moving/observer at rest Source/observer moving Observer moving/source at rest

Source moving/observer at rest Source/observer moving Observer moving/source at rest

Efekt Dopplera dla ruchu źródła Zagęszczenie frontów falowych i wreszcie…

Efekt Dopplera dla ruchu źródła Zagęszczenie frontów falowych i wreszcie…

BUM!!! czyli przekroczenie bariery dźwięku

BUM!!! czyli przekroczenie bariery dźwięku

Applications Ø Ø Ø Other important applications of the Doppler Effect: Doppler Radar uses

Applications Ø Ø Ø Other important applications of the Doppler Effect: Doppler Radar uses the doppler effect for electromagetic waves to predict the weather. The Doppler shift for light is used to help astronomers discover new planets and binary stars. Echocardiography - a medical test using ultrasound and Doppler techniques to visualize the structure of the heart. Radio Direction Finding Systems There is also an instrumental rock group called The Doppler Effect

Standing wave in pipes Superpozycja identycznych, przeciwbieżnych fal

Standing wave in pipes Superpozycja identycznych, przeciwbieżnych fal

Standing wave in strings

Standing wave in strings

Standing wave in strings

Standing wave in strings

Zdudnianie się fal

Zdudnianie się fal

Rejestracja dudnień Detektor

Rejestracja dudnień Detektor