Ready for action?
Resources
Tangible Resources
Sound absorbing materials (glass, fabric, polystyrene, wood chips, acoustic foam, sponge, granular materials), decibel meter, boxes to construct a soundproof chamber, board or plywood to make a model of a house with acoustic insulation, smartphones.
Preparation
Prepare materials and resources.
Goals, messages & concepts
Specific goals
- Understand the importance of noise protection and acoustic comfort.
- Know how to test various materials in terms of absorption of sounds at high and low frequency.
- Know how to use these materials for acoustic insulation of rooms, e.g. house insulation against noise from the surroundings.
Specific messages
- Different materials have different sound-reducing properties.
- The theory of sound learnt so far has real-world applications.
Main terms
- noise
- acoustics
- material properties
- acoustic insulation
Practices & skills
STEM practices
- Analysing and interpreting data
- Constructing explanations and designing solutions
- Developing and using models
- Engaging in argument from evidence
- Obtaining, evaluating, and communicating information
- Asking questions and defining problems
- Planning and carrying out investigations
Soft skills
- Teamwork and collaboration
Management skills
- Planning
- Use of resources
Course of activity
step 1
Introduce students to the topic of reducing background noise and stress the importance of acoustic comfort in the rooms students are in and how they can take care of it. Explain the purpose of the activity and the tasks to be carried out, then students will take the necessary materials and carry out measurements and calculations.
step 2
Each group will place a smartphone in an empty box with a sound of a certain frequency playing, and then measure the intensity of the sound. The result should be noted. The measurement should be performed for high and low frequency.
step 3
Students then line their boxes with different materials, place a smartphone in the sound-absorbing chamber thus prepared, with the same frequency of sound as before - one high and one low. Students learnt to gather consistent data in Learning Unit 7 – they should apply this by placing the decibel meter at the same distance from the box as before to measure the intensity level of the sound coming out of the box. Results should be recorded.
step 4
Students will repeat the experiment by increasing the thickness of the absorbing material.
step 5
Based on the results, students will calculate the sound intensity for each measurement and the sound absorption coefficients for their selected materials. Students will note whether it’s different for high frequency sounds and low frequency sounds.
step 6
A representative from each group will present their measurement results to the class, writing them on the board/large sheet of paper in a prepared table which includes the type of material, its thickness and the sound absorption coefficient for each of the two frequencies tested. The table will be used to select insulating materials when designing the house.
step 7
Students will design acoustic insulation for a model house, paying attention to windows (glass panes, what the space between the panes should be filled with), walls, ceiling and floor. They will also calculate the costs of such insulation.
step 8
They then have the opportunity to construct a model of their sound-absorbing house design.