Introduction

An investigation into resonance and standing waves

Waves form the basis of many phenomena in physics, being a joy in music and a cause for concern in structures as well as one half of the dual nature of light and matter. To understand waves, it is important to know the basic properties of waves and how simple waves can interfere to produce more complex waves. The superposition of waves as they interfere is fundamental to the formation of standing waves which can produce beautiful harmonies or destroy bridges.

Program Overview

In this investigation students will analyse the nature of waves in different medium, the factors effecting the formation of standing waves in strings, air columns and plates and how this is linked to the production of music and run-away resonance in structures.

Students will use wave driver on strings under tension to investigate the factors effecting the formation of standing waves in strings and how this will reinforce a applied vibration. They will then use a Kundt’s apparatus to analyse the formation and nature of standing waves in air columns and its relation to various musical instruments. The data generated from these cases can be related to standing waves in other situations and the behaviour of light as a wave.

An extension task allows the analysis of standing waves in two dimensions using Chladni Plate.

This program offers various starting off points for student experimental investigations.

Curriculum Focus

Unit 4 Area of Study 1 – How has understanding about the physical world changed?

Light as a wave

• describe light as a transverse electromagnetic
• explain the formation of a standing wave resulting from the superposition of a travelling wave and its reflection
• analyse the formation of standing waves

Unit 4 Area of Study 2 -How is scientific inquiry used to investigate fields, motion or light?

Investigation design

• explain the characteristics of the selected scientific methodology and method including:
  • techniques of primary qualitative and quantitative data generation;
  • appropriateness of the use of independent, dependent and controlled variables
• identification of, and distinction between, error and uncertainty
• identify and apply health, safety and ethical guidelines relevant to the selected investigation

Scientific evidence

• apply methods of organising, analysing and evaluating primary data to identify patterns and relationships including:
  • the physical significance of the gradient of linearised data;
  • causes of uncertainty