Sssshhhh!

Investigate the sound-insulating properties of various materials.

Make sure that the volume is at a sensible level.  Do not play the music too loudly - or where it will annoy others.  Be considerate as well as safe!

PLAN

EITHER

Design an "insulating chamber" - in which you can place a loud-speaker surrounded by insulating material.

OR

Design some ear-muffs (so that you can change the padding material) - or perhaps you could make lots of pairs.

I WILL NEED

An adjustable "sound-source" (a cassette player or CD player).

Various materials for testing (e.g.: piece of cotton material; knitted wool; cotton wool, polystyrene beads; crumpled paper; etc.)

Pencil and paper.

I MAY NEED

Something to act as an "insulating chamber" (e.g.: biscuit tin).

CLICK HERE to see a sample

INSULATING CHAMBER

FAIR TEST

Who is going to judge when the sound can be heard?

How can you be sure that the sound you are producing is at an even level (without any quiet bits or gaps between songs, for instance).

If you use the "ear-muffs", how can you be sure that the amount of insulating material is the same for each set?

PREDICTION

Which of the materials do you think will be the best sound insulator?

Which do you think will be the worst?

PRACTICAL ACTIVITY

Place some of your first insulating material in the chamber (or the ear-muffs).

Gradually increase the volume of the "sound-maker" until you can just hear it.

Note the sound level.

Repeat with different insulating materials.

COLLECT

DATA

For each material, record the volume-level of the sound-source at the point that the sound is just audible.

ANALYSE

DATA

What does your data tell you?

PRESENT

FINDINGS

Explain clearly what you did.

Would a diagram make things clearer?

Is it possible to give a demonstration?

What is the best way to show your findings?

EVALUATE

INVESTIGATION

Were you completely satisfied that every part of the investigation was carried out fairly?

What else could you have done to get a fairer result?

How could you have recorded the sound levels more accurately?

If you have carried out this investigation, click the icon to send in your results to Brainboxx and we may publish your work on the website.  It is best to e-mail the results of your investigation or you may need to send them by post.  Make sure you get permission from a teacher, parent or other adult before you get in touch.

SOUND BASICS

SOUND QUIZ