Waves3 - Wave Wave a disturbance that propagates that...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Wave Wave a disturbance that propagates that through a material medium or through medium space. space In order for a mechanical wave to exist, In mechanical energy is needed to create a energy disturbance in an elastic medium. disturbance elastic Waves transfer energy Waves transfer without without the bulk transport of matter. No medium is needed for No ELECTROMAGNETIC waves. waves. Light, radio, x-rays, and gamma Light, rays rays are some examples of e/m waves. are All e/m waves travel through free All travel space at a speed of approximately 3.00 x 108 m/s or 186,000 miles/sec. or This speed is known as the speed of light. light TRANSVERSE The displacement of the particles The of the medium is perpendicular to perpendicular to the direction of wave propagation. LONGITU DINAL The displacement of the particles of the medium is parallel to the is parallel to direction of wave propagation. SU RFACE A combination of combination transverse and longitudinal. transverse longitudinal Click here, here, and here to view simulations of transverse and longitudinal waves. Amplitude Amplitude the maximum displacement the maximum of a particle of the medium from of the rest or equilibrium position denoted by A and measured in units of length Phase Phase related to the position and motion related position of the particles of the medium Wavelength Wavelength the shortest distance between the shortest two points that are “in phase” denoted by λ and measured in units of length denoted Frequency - the number of complete Frequency vibrations per unit time vibrations denoted by f and measured in units of Hz Period - the shortest time interval during time which the motion of the wave repeats itself denoted by T and measured in units of time T = 1/f & f = 1/T Velocity - the speed of the wave speed Velocity denoted by v and measured in units of dist/time The speed of a wave depends on the properties of the medium through which it is traveling. v = d/t = λ /T = f λ Reflection the turning back of a wave when the turning it reaches the boundary of the it boundary medium through which it is traveling Law of Reflection the angle of incidence is equal the angle equal to the angle of reflection to angle There are two types of reflection. Fixed-end Termination the reflected wave is inverted when it reflects from a more dense medium Free-end Termination the reflected wave is upright when it reflects from a less dense medium Click here to view these types of reflection. Click here Refraction the bending of a wave as it bending passes obliquely from one obliquely medium into another of different propagation speed different For refraction to occur, the wave must change speed and must enter the new medium at an oblique angle. Diffraction Diffraction the spreading of a wave spreading of around a barrier or through an opening Interference the result of the superposition the superposition of two or more waves Superposition Principle the displacement of the medium when two or more waves pass through it at the same time is the algebraic it algebraic sum of the displacements caused by the individual waves Types of Interference Constructive Constructive results in a larger amplitude larger Destructive results in a smaller amplitude smaller Read more about interference here. here Click here to view the interference Click here pattern resulting from the superposition of two transverse waves. Click here and here to view Click here here simulations of the interference of two circular waves. The ripple tank simulation found here can be used to investigate wave properties. You can view reflection, You refraction, diffraction, and interference using both plane and circular waves. Click here to view a movie Click here clip of an actual ripple tank experiment. A standing wave is the standing result of two wave trains of the same wavelength, frequency, and amplitude traveling in opposite directions through the same medium. Learn more about standing waves here, here, and here. Click here to view a simulation of the interference of two traveling waves that can result in a standing wave. Click here to view a simulation of standing waves on a string. Standing waves may be produced easily in water, string, and air columns. Doppler Effect Doppler the change in frequency due to the relative motion of the wave source and the observer The observed frequency is higher when the The observed higher source and observer are getting closer. source closer The observed frequency is lower when the The observed lower source and observer are getting farther away. source away Click here, here, here, and here here here here and here to run simulations of the Doppler Effect. The Doppler Effect can be evident for all types of waves – including light, sound, water, etc… ...
View Full Document

This note was uploaded on 11/08/2011 for the course PHYSICS 121 taught by Professor Richardvanfleet during the Winter '09 term at BYU.

Ask a homework question - tutors are online