Year 4 Science - Sound Activity 1 - Vibrations - Page 2 Activity 2 - PowerPoint PPT Presentation

Year 4 – Science - Sound Activity 1 - Vibrations - Page 2 Activity 2 – How do we hear? - Page 8 Activity 3 – Loud and quiet sounds - Page 15 Activity 4 - Pitch - Page 21 Activity 5 – Pitch Optional Challenge – Page 30 Activity 6 - Quiz - Page 33

What is Sound? Discuss with your family or think about what you already know using the questions below as prompts.

What is Sound? Watch this clip to see to see how the different families of musical instrument create different sounds. https://www.bbc.co.uk/bitesize/clips/zqtxpv4 How do the musical instruments make sounds? Think of some words you could use to explain this.

What is Sound? Did you come up with some words to explain how the musical instruments make sounds? Look at the words below. Did you choose any of these words? Vibrate Vibration Twang Blow Bang Scrape Shake Pluck

Vibrations All the instruments are played in different ways, but they all have something in common. They all create sounds by vibrating. The strings of the guitar and the gopichand vibrate when they are plucked. The pan pipes and horn are filled with air, which vibrates when they are blown. The balafon and the bongos make sounds when they are hit or banged, causing the blocks or the skin to vibrate. But what is a vibration?

Vibrations We can see and feel vibrations whenever sounds are made. Gently place your hand on your throat. Say ‘Ah!’ Can you feel the vibrations from your vocal cords? Ahh

Sound Survey Around your home or on your daily walk there are lots of different sounds. Some places will be noisy, whereas some places will be quiet. The loudness of the different places will even change throughout the day! You are going to carry out a sound survey of your home or local area to find which places are noisy and which are quiet at different times of day. You may decide to rate each place out of 5, with 5 being very noisy and 0 being totally silent. (Science Tasks Document page 1)

What did you learn about in activity 1?

What did you learn about in activity 1? We know that vibrations create sounds but how do we hear these sounds?

Watch this video to find out more https://www.bbc.co.uk/teach/class-clips- video/music--science-ks2-what-is- sound/zbnmhbk

How sound is made? Sound is caused by vibration. Vibration means wobbling very quickly back and forth. When you pluck a guitar string, or hit a drumskin, you can see the material vibrate. This causes the air touching the string to vibrate, which causes air further away to vibrate, which causes the air near your ear to vibrate, which your brain experiences as sound. The moving vibration is called a sound wave.

How our ears work When a sound wave reaches our ear, our outer ear (the part that we can see on the side of our heads) funnels the sound into our heads down the ear canal. At the end of the ear canal is the eardrum, which is waterproof and airtight. Past the ear canal is the middle ear. Inside the middle ear are the hammer, anvil and stirrup (the three smallest bones in the body) which vibrate and pass the sound waves to the inner ear, which contains the cochlea, which turns the vibrations into electrical signals. These signals travel down the auditory nerve to the brain, which experiences the signal as sound.

Activity 2 Using the information on the slides and the video, create an explanation text showing how we hear things. You could use the sheet (Science Tasks Document page 2-3) For an extra challenge, try drawing some of your own diagrams and writing some of your own descriptions.

Vibrations We know that sounds are made when something vibrates. What is vibrating in each of these pictures to make a sound?

Loud and quiet sounds Watch this clip to see if you can identify how different sounds travel. https://www.bbc.co.uk/bitesize/clips/z9h6n39

Loud and Quiet The louder the sound, the bigger the vibration. In the video, you should have noticed that the polystyrene balls vibrated more when she hit the drum harder, creating a louder sound. The size of the vibration is called the amplitude. Quieter sounds have a smaller amplitude, and louder sounds have a bigger amplitude.

How Does Sound Travel? Sound can travel through solids, liquids and gases. Sound travels as a wave, vibrating the particles in the medium it is travelling in. So in our example, when she hit the drum, the drum skin vibrated. This made the air particles closest to the drum start to vibrate as well. The vibrations then passed to the next air particle, then the next, then the next. This carried on until the air particles closest to your ear vibrated, passing the vibrations into your ear.

Hearing Sounds Once in your ear, the vibrations travel into the ear canal until they reach the eardrum. The eardrum passes the vibrations through the middle ear bones (the hammer, the anvil and the stirrup) into the inner ear. The inner ear is shaped like a snail and is called the cochlea. Inside the cochlea, there are thousands of tiny hair cells. Hair cells change the vibrations into electrical signals that are sent to the brain through the hearing nerve. The brain tells you that you are hearing a sound and what that sound is.

The Science of Sound Activity Use the ideas you saw in the clip, or your own ideas to come up with your own way of explaining how different sounds travel for the programme. You could use The Science of Sound Activity Sheet (Science Tasks Document page 4) to plan your ideas and then practise what you will do and say. Make sure your explanations are clear and easy for children to understand. Have fun and get into character!

Different Sounds Sounds can be loud or quiet. Bigger vibrations make louder sounds, and smaller vibrations make quieter sounds. There are other ways sounds can be different. Can you make a high sound? How about a low sound?

Different Sounds High and low are words to describe the pitch of a sound. The pitch of a sound is different to the amplitude. Amplitude is a measure of how loud or quiet a sound is, and pitch is a measure of how high or low a sound is. High sounds can be quiet or loud, and low sounds can be quiet or loud too! Amplitude Pitch

Different Sounds Watch this clip to see if you can hear and identify how different musical instruments create different sounds. https://www.bbc.co.uk/bitesize/clips/zsqw2hv

Changing Pitch Watch this clip explaining how the pitch of a sound can be changed. https://www.bbc.co.uk/bitesize/clips/ztptsbk

Changing Pitch On a string instrument, there are several ways to change the pitch. The tighter, thinner or shorter the string is, the higher pitched the sound will be and the looser, thicker or longer the string is, the lower the sound will be. Faster vibrations will make a sound higher, and slower vibrations will make a sound lower. The ways of changing the strings all change the vibrations, which in turn change the pitch of the sound.

Changing Pitch On a wind instrument, the column of air inside the instrument is what vibrates to cause the sound. Shortening the column of air will create a higher sound, and lengthening the column of air will create a lower sound. This can be done with a sliding mechanism, such as in a trombone. The length of the column of air can be changed by opening or closing holes in the side of the tube, such as in a recorder.

Changing Pitch In a percussion instrument, the surface or object that is struck is the thing that vibrates to create the sound. The pitch of a percussion instrument can be changed in different ways. There may be a series of different length bars or keys, such as in a xylophone. The shorter the bar or key, the higher the pitch will be. There may be different instruments of different sizes. For example, when playing hand bells the musician will have a set of bells to play. The smaller the bell, the higher the pitch. The larger the bell, the lower the pitch. In a drum, the tighter the skin, the higher the pitch will be. A thinner skin will make a higher pitched sound and a thicker skin will make a lower pitched sound.

Changing Pitch Do you notice anything in common with how the different instruments create sounds of different pitches? Generally, the shorter, tighter or thinner the object is, the higher the pitch of the sound will be. This is because the vibrations will be faster. The longer, looser or thicker the object is, the lower the pitch of the sound will be. This is because the vibrations will be slower.

Pitch Investigation Activity Look at the investigation. (Science Tasks Document page 5. Can a straw produce different sounds?

Pan Pipes Challenge Your challenge is to create a set of pan pipes that will create sounds of different pitches, and explain how to change the pitch. You will use straws, scissors, sticky tape and string to make the pan pipes.

Pan Pipes Challenge Flatten the end 2cm of each straw, and cut a triangle in the end, like this. Place the triangular end of the straw in your mouth and blow hard through the straw to make a sound. You may have to try few times to make the sound! Use several straws to make your set of pan pipes. Stick or tie them together. Think about what you have learnt in order to make each straw make a different pitched sound.