How sounds are sent and received by our ears, and some simple activities to investigate it, are explained by Pat Brunton and Linda Thornton

 

The ability to hear and make sounds helps us to gain information about what is going on in our environment, as well as to communicate with one another.

From early age, children will be aware of sounds all around them - voices, body sounds, weather, animals, vehicles, machinery, music, TV and toys. They will know that sounds are used to convey messages - for example, sirens warn of danger, radio and TV broadcasts provide information and entertainment, music affects our mood and emotions, and talking and listening enable the exchange of knowledge and experience.

 

What do I need to know?

Use the information below to inform your planning and help you support young children's scientific exploration. But remember, it is not intended that children in the Foundation Stage are taught these facts.

How are sounds made?

All sounds are caused by small repeated movements called vibrations. For example, when we speak, our 'voice box' vibrates. When an engine is running the metal parts of the engine are vibrating, and when a radio is playing the metal and plastic parts of the speakers are vibrating. All musical instruments create sound through vibrations.

The different sounds that instruments make depend on what they are made of and how the vibrations are created. A drum creates a sound when the skin of the drum is struck with a drumstick, making the surface of the drum start to vibrate. When the string on a guitar is plucked it starts to vibrate, and when you blow into a clarinet the bamboo reed in the top of the instrument begins to vibrate.

In all these examples the vibrations, or small mechanical movements, make the material surrounding them vibrate. The term 'sound wave' is used to describe these vibrations.

We hear a sound when the sound wave reaches our ears. Usually the sound waves travel through air from the object creating the sound to our ear.

Sound can also travel through solid objects and through water. If you put your ear up against a door you can hear what is happening on the other side. If you put your head under water in the bath and then tap on the side of the bath, you can hear the sound of the tapping very clearly.

How do we hear?

Sound waves travel in all directions from the object making the sound. Some of these sound waves reach our ears and make the surface of our eardrum vibrate. These vibrations are transmitted through the inner ears to nerve cells, which then pass a message to the brain. When this message reaches the brain we 'hear' the sound.

Sound waves travel in straight lines, so it is easier to hear something if you turn so your ear is facing the sound. Animals such as dogs, horses and deer, which rely heavily on their sense of hearing, have ears which can swivel round to face in different directions. The more sound waves that reach the ear, the easier it is to hear quiet sounds. Some animals, such as foxes, rabbits and mice, have large ears so they can pick up sounds more easily.

When sound waves hit a solid object such as a wall or a mountainside, they bounce off again. Sometimes this creates an echo, as you hear two versions of a sound - one that reaches your ear directly, and one that has travelled some distance, hit a solid object and then bounced back to your ear.

Loud and soft, high and low

Volume is the term used when talking about how loud or soft a sound is.

Loud sounds create lots of big vibrations and soft sounds create fewer, smaller vibrations. The distance the sound wave has to travel before it reaches our ear also affects how loud it sounds. Sounds that are made further away seem quieter to us.

Pitch is the term used to describe how high or low a sound is. High-pitched sounds create fast vibrations which are very close together. Low-pitched sounds create slower vibrations which are more spaced out. You can get an idea of this on a guitar if you look at the way in which the high and the low strings behave when they are plucked.

Children with hearing difficulties

Young children may have hearing impairments, either temporary or permanent, for various reasons. Those children who are unable to hear sound need lots of opportunities to experience sound vibrations, so they can feel what different sounds are like.

Investigating

On the line

What you need: Kitchen utensils hung from a washing line at child height - include large and small utensils and ones made from different materials, such as wooden spoons, metal ladles and plastic tongs.

What to do

  • Look at the kitchen utensils with the children and talk about what they are for, how you would use them and what they are made of.
  • Encourage the children to sort the utensils by material that they are made of.
  • Introduce the idea of making a musical washing line.
  • Ask the children to choose from each group a selection of utensils that they think would work well on the 'musical' washing line.
  • Help the children to hang the utensils on the line, evenly spaced.
  • Choose a utensil to use as a beater and investigate the sounds that the tools make when struck. Which ones make a loud/soft noise? Which ones make a high/low sound? What happens when you use a beater made of a different material? Could you play a tune on your musical washing line? Can you make a 'kitchen band'?

 

Speaking tube

What you need: A selection of books and pictures showing animals with large ears; length of plastic tubing - hosepipe or fish pond tubing works well; two large plastic funnels which fit snugly into the ends of the tubing.

What to do

  • Talk to the children about listening to different sounds and help them to think about which parts of their bodies they use to make sounds and which parts they use to hear sounds.
  • Ask the children to sit quietly indoors, close their eyes and listen carefully to the sounds they can hear. Talk about these sounds and help the children to identify them.
  • Look at the pictures of animals with large ears and talk about how they use their ears to hear quiet sounds.
  • Help the children to investigate what happens if you cup your hand behind your ear and then listen to a sound. Is it easier to hear soft sounds?
  • Investigate the tubing with the children. Try holding one end close to your ear and speak quietly into the other end. Warn the children not to shout!
  • Push the funnels into either end of the tubing. Encourage one child to hold one of the funnels to their ear, and another child to speak quietly into the other funnel.
  • Help them to experiment with talking and listening to each other through the tube. Try using your tube outside, or for communicating between one part of the setting and another.

 

Vocabulary to introduce

sound listen ear

loud speak mouth

soft shout music

high whisper funnel

low talk tube

 

Further information

Linda Thornton and Pat Brunton are education consultants with a special interest in science and technology for young children. Contact them at www.alcassociates.co.uk.