Last week as part of our science unit, “Invisible Forces”, we had fun exploring sound waves and vibrations. We’d touched on this topic last year as part of a music workshop session that my mum ran for us, but it was good to refresh the girls’ knowledge and find some more fun activities for some fabulous hands-on learning.
The girls always learn best when they are creative, moving about and engaged, with activities and resources that either fascinate them or make them giggle. These activities seem to provide them with a “mental peg” on which to hang the concept taught in the lesson and this helps with both memory/retrieval of a concept and also with drawing links between concepts across subject areas.
So set these quick, easy challenges this week – have on hand arnica (for bumps and bruises) and ear plugs (for your own sanity)…
- Use a balloon to demonstrate that sound causes vibrations. You can do this simply by placing your fingers on your larynx to feel the vibrations caused when you are speaking. Using a balloon takes things a step further showing that sound waves travel through air to cause vibrations that you can feel when you hold the balloon and sing/shout into it. Encourage your child to experiment with different pitches, sounds and varying volume.
- Make a simple paper cup telephone to explore how sound waves travel through a medium across distances. Take two paper cups and make a small hole in the bottom of each. Pass one end of a length of string through the hole in each cup and anchor it in place using a paper clip. Ask the children to play around with sending messages to each other. Get them to experiment over different distances, around corners, with varying tensions in the string, perhaps even try different materials (e.g. paper or plastic cups, different thicknesses of string, or wool, or wire). Set them a challenge to create a three- or four-way telephone. Reflect on what works best and whether certain sounds travel better than others. (Exquisite rays of evening sunlight are an optional extra 🙂 )
- Play this crazy game to show how sound waves pass through the air: one person is the sound source and the other people line up in front of them pretending to be particles of air. The sound source person creates a ‘sound’ and physically pushes the person in front of them, who crashes into the person in front of them and so on, thus recreating the effect of a sound wave passing through the air. You can extend this by demonstrating the effect of an echo if the line of people/air particles approaches a wall. When the sound wave reaches the person at the end of the line , she/he crashes into the wall and bounces back to the person behind them and so on, passing the ‘echo’ back to the sound source. *WARNING* this game has the potential to be become wild, noisy, bumpy and hilarious. Play this game at your own risk. It is not for the faint-hearted. (Sorry – no pics of this because I was being an air particle 😉 )
- Use a skipping rope tied to a table or chair leg to explore transverse waves – you will cause the vibrations to pass through the rope by wiggling one end of it from side to side. You might want to look at some pictures of high/low pitch sound waves, and then ask your children to recreate these waves in the rope. Get your children to experiment and discuss with them what they needed to do to create high/low pitch waves (i.e. the faster you jiggle the rope, the shorter the wavelength, the higher the pitch/frequency; the slower you wiggle it, the longer the wavelength, the lower pitch/frequency).
- Explore sounds using this fabulous online oscillator. Once you’ve got this set up it provides hours of fun. Ask your children to experiment with different sounds and volumes – look closely at the difference between speech versus song/an instrument playing, and other percussive noises such as clapping, banging, drumming. Examine the difference between high/low frequency (pitch – notice the difference in wavelength), loud/soft sounds (volume – notice the difference in amplitude) and also between pure tones (such as a sung vowel sound or a note played on an instrument) which produce regular, periodic, sinusoidal wave forms (nice link here to a spot of trigonometry 🙂 ) and sounds that create more irregular (aperiodic) wave patterns.
If this has sparked your kids’ interest then you might find this link useful and just to finish off, we enjoyed watching these videos together to explore this topic further: