Normal Modes

Normal Modes Screenshot
  • Oscillator
  • Normal Modes
  • Polarization

Topics

  • Oscillator
  • Normal Modes
  • Polarization
  • Mass Spring System
  • Frequency
  • Amplitude
  • Phase

Description

Play with a 1D or 2D system of coupled mass-spring oscillators. Vary the number of masses, set the initial conditions, and watch the system evolve. See the spectrum of normal modes for arbitrary motion. See longitudinal or transverse modes in the 1D system.

Sample Learning Goals

  • Explain what a normal mode is.
  • Explain what are the frequency, the amplitude, and the phase of a normal mode.
  • Explain why different normal modes have different frequencies and why higher-numbered modes have higher frequencies.
  • Identify how many normal modes a given system has and be able to sketch the individual modes qualitatively, for both 1D and 2D systems.
  • Explain the distinction between transverse and longitudinal normal modes in a 1D system.
  • Explain how adjusting the phase of a normal mode affects the motion of the system.
  • Explain qualitatively how any arbitrary state of the system can be written as a sum of normal modes; that is, explain the superposition principle.
  • Explain which properties of the system are set by the initial conditions, which properties are time-independent, and which properties are time-dependent.
  • Explain why striking a metal plate in one spot raises the temperature of the plate.
Version 1.01

Teacher Tips

Download teacher tips PDF Overview of sim controls, model simplifications, and insights into student thinking ( PDF ).

Teacher-Submitted Activities

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Language Download or Run Tips
Basque All Euskara Run now Bibrazio-modu normalak
Belarusian All беларускі Run now Нармальныя рэжымы
Bosnian All Bosanski Run now Normalni modovi
Chinese (Simplified) All 中文 (中国) Run now 标准振荡
Chinese (Traditional) All 中文 (台灣) Run now Normal Modes 正規振態
Danish All Dansk Run now Normalindstillinger
French All français Run now Modes vibratoires à plusieurs corps
Galician All Gallegan Run now Modos de vibración
German All Deutsch Run now Normalschwingungen 1D & 2D
Greek All Ελληνικά Run now Κανονικές καταστάσεις
Hebrew All עברית Run now מצבים נורמלים
Hungarian All magyar Run now Normál módusok
Indonesian All Bahasa Indonesia Run now Pola - pola Normal
Italian All italiano Run now Modi normali di vibrazione (Risonanza)
Japanese All 日本語 Run now 基準振動(モード)
Kannada All Kannada Run now ಲಂಭ ಬಹುವರ್ತಿ(ಮೋಡ್)
Kazakh All Kazakh Run now қалыпты тізімдер
Korean All 한국어 Run now 정규 모드
Macedonian All македонски Run now Нормални модови
Mongolian All Монгол (Монгол) Run now Хэвийн Горим
Persian All فارسی Run now مد طبيعي
Polish All polski Run now Mody Normalne
Portuguese (Brazil) All português (Brasil) Run now Modos Normais
Serbian All Српски Run now Нормални модови
Slovak All Slovenčina Run now Normálne vibračné módy
Spanish All español Run now Frecuencias resonantes. Download teacher tips PDF
Spanish (Mexico) All español (México) Run now Frecuencias resonantes. Download teacher tips PDF
Spanish (Peru) All español (Perú) Run now Frecuencias Resonantes
Thai All ไทย Run now โหมดปกติ
Turkmen All Turkmen Run now Yrgyldamanyň normal diapazonlary
Vietnamese All Tiếng Việt Run now Kiểu dao động chuẩn tắc

Windows Macintosh Linux
Microsoft Windows
XP/Vista/7/8.1/10
Macromedia Flash 9 or later
OS X 10.9.5 or later
Macromedia Flash 9 or later
Macromedia Flash 9 or later

Design Team Third-party Libraries Thanks To
  • Michael Dubson (lead designer/developer)
  • Jon Olson (developer)
  • Ariel Paul (development/interviews)
  • Trish Loeblein (development)