### About

### For Teachers

### Translations

Code | Language | Translator | Run | |
---|---|---|---|---|

### Software Requirements

Android | iOS | Windows | MacOS | |

with best with | Chrome | Chrome | Chrome | Chrome |

support full-screen? | Yes. Chrome/Opera No. Firefox/ Samsung Internet | Not yet | Yes | Yes |

cannot work on | some mobile browser that don't understand JavaScript such as..... | cannot work on Internet Explorer 9 and below |

### Credits

Andrew Duffy; lookang; tina

### end faq

## Apps

### Description

Introduction

Wave is an oscillation accompanied by a transfer of energy that travels through medium (space or mass)

Waves consist, instead, of oscillations or vibrations (of a physical quantity), around almost fixed locations

This simulation is on transverse wave where disturbance creates oscillations that are perpendicular to the propagation of energy transfer.

The equation for wave is A sin ( wt +kx + ϕ)

where

A is the maximum amplitude of the wave, maximum distance from the highest point of the disturbance in the medium (the crest) to the equilibrium point during one wave cycle.

w is is the angular frequency

t is time

k is is the wavenumber

x is the position

ϕ is the is the phase constant

concepts illustrated in the simulations include

T is the time for one complete cycle of an oscillation of a wave

f is the number of periods per unit time (per second) and is related by T = 1/f

λ is the wavelength

v is the velocity of the wave travelling and is related by v= f λ

vtmax is the maximum transverse velocity of the wave particle that occurs at the displacement d =0.

### Examples

EJSS wave representation model

Equation used to model the wave is \( y = A sin ( \omega t - k x ) \)

## Amplitude A

amplitude of wave = 0.18 m, maximum displacement from equilibrium position http://iwant2study.org/ospsg/index.php/112 Direct Link |

amplitude of wave = 0.20 m, maximum displacement from equilibrium position author: Andrew Duffy, lookang, tina author EJS: Francisco Esquembre |

## wavelength λ

wavelength of wave = 1.70 m The wavelength λ wavelength is the distance between two sequential crests or troughs (or other equivalent points) |

wavelength of wave = 0.50 m The wavelength λ wavelength is the distance between two sequential crests or troughs (or other equivalent points) author: Andrew Duffy, lookang, tina author EJS: Francisco Esquembre |

## Period T

period of wave = 3.00 s, The period T is the time for one complete cycle of an oscillation of a wave http://iwant2study.org/ospsg/index.php/112 Direct Link |

period of wave = 3.00 s, The period T is the time for one complete cycle of an oscillation of a wave author: Andrew Duffy, lookang, tina author EJS: Francisco Esquembre |

## angular frequency f

The frequency f = 1/T is the number of periods per unit time (per second) and is typically measured in hertz http://iwant2study.org/ospsg/index.php/112 Direct Link |

The frequency f = 1/T is the number of periods per unit time (per second) and is typically measured in hertz author: Andrew Duffy, lookang, tina author EJS: Francisco Esquembre |

## angular velocity of wave ω

angular frequencyω = 2.09 s, The angular frequencyω represents the frequency in radians per second. http://iwant2study.org/ospsg/index.php/112 Direct Link |

angular frequencyω = 2.09 s, The angular frequencyω represents the frequency in radians per second. author: Andrew Duffy, lookang, tina author EJS: Francisco Esquembre |

## phase difference ϕ

the phase of a vibration (that is, its position within the vibration cycle) ϕ measured in radians taking ratio "ϕ/(2π)= Δt/T", ϕ = 2π(2.5-0.75)/3 =3.7 rad approximately |

## wave speed v

sinusoidal waveform traveling at constant speed v is given by v = f λ http://iwant2study.org/ospsg/index.php/112 Direct Link |

sinusoidal waveform traveling at constant speed v is given by v = f λ author: Andrew Duffy, lookang, tina author EJS: Francisco Esquembre |

## maximum transverse speed vmax

The maximum transverse velocity is vmax = Aω and it occurs when the particle on the wave travels passes through the equilibrium position http://iwant2study.org/ospsg/index.php/112 Direct Link |

The maximum transverse velocity is vmax = Aω and it occurs when the particle on the wave travels passes through the equilibrium position author: Andrew Duffy, lookang, tina author EJS: Francisco Esquembre |

## reference:

http://weelookang.blogspot.sg/2011/04/ejs-open-source-wave-representations.html

### Video

### Versions

- http://weelookang.blogspot.sg/2015/08/ejss-wave-representation-model.html Blog post of JavaScript version of Wave Representations by Andrew Duffy and Loo Kang Wee
- http://weelookang.blogspot.sg/2011/04/ejs-open-source-wave-representations.html Blog post of Java version of Wave Representations by Andrew Duffy and Loo Kang Wee
- http://iwant2study.org/lookangejss/04waves_12generalwaves/ejs/ejs_model_Wave_representations_v5.jar Java version of Wave Representations by Andrew Duffy and Loo Kang Wee

### Other Resources

- http://physics.bu.edu/~duffy/HTML5/wave_movie_and_graph.htmlby Andrew Duffy
- http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2405.0 One dimensional moving wave y(x,t)=A sin(k*x-w*t) by Fu-Kwun Hwang