Hello, this is Mr. James, and I'm very much looking forward to learning some science with you today.

I hope that you are feeling curious.

And if you are, then we're all set.

We're ready to go.

Our lesson is from the Unit: Introduction to Sound.

And today's lesson is called "Louder and quieter sounds." Our learning outcome for this lesson is: I can compare the volume of different sounds and identify loud and quiet sounds.

We'll need some key words to help us with our learning.

Here's the first one.

You can repeat it after me.

Vibrations.

Loud.

Quiet.

Volume.

Compare.

Here are the meanings of those words.

You can read them and if you need to, pause the video for a few moments.

But don't forget, you can always come back to them during the lesson if you need to check them.

Pause the video now if you need to.

So here's the outline for today's lesson.

We're gonna start with sound vibrations, and then we'll move on for the second part to volume of sounds.

How are sounds made? Discuss this with a partner.

Pause the video now.

Did you have similar ideas or were there some differences? I wonder.

Sounds are made when an object vibrates.

Look at the pictures below.

What's vibrating to create the sound.

So we have playing a glockenspiel or speaking into a string telephone.

What's vibrating for each of those images? You can pause the video if you want to talk about that.

Do you know what vibrates when a piano is played? When you press a piano key, a tiny hammer inside the piano strikes a string and the string vibrates.

This makes a musical sound.

You can see the strings inside a piano in the second picture here.

The vibrating strings make the sides of the piano vibrate, which makes the sound louder.

How do we hear sounds? When an object vibrates, the vibrations travel through a medium such as a solid, a liquid, or a gas.

The vibrations then travel to the person's eardrum and causes this to vibrate, allowing them to hear the sound.

You can see a human eardrum here in the picture.

So how are sounds made? A, when we hear them.

B, when an object vibrates.

Or C, inside the object and then released into the air.

What do you think? Yes, it's when an object vibrates.

Lucas has been thinking, "Sometimes I can make really loud sounds and then sometimes I can make quiet sounds.

How does this happen?" Do you have any ideas why? Pause the video now so you can talk about this.

Aisha says, "I think the loudness of sounds depends on the size of the object that's vibrating." What do you think? Pause the video if you need to.

A large drum hit with the same force as a small drum will sound louder.

This is because the larger drum has a larger skin which will create bigger vibrations that travel to our ears.

Aisha thinks, "Other things can affect how loud or quieter sound is, not just its size.

When I tap my foot on the floor gently, I make a quiet sound, but when I stamp my foot hard, it makes a loud sound." Do you know why this happens? Pause the video if you need to talk about that.

Lucas says, "I think the loudness of sounds also depends on the size of the vibrations." "When I shake my baby's sisters rattle really hard, the sound is loud," thinks Lucas.

"That's because the vibrations are larger when you shake, hit, or blow something harder," Aisha explains.

"So, the vibrations must be smaller when I shake the rattle gently and the sound is quiet." We're going to watch a video clip now.

It shows a type of bell.

It's called a singing bowl.

And this singing bowl makes sounds using a small mallet.

(bowl vibrates) I wonder what you thought of that sound.

I'd rather like it.

Can you explain to your partner how could you make these sounds louder and quieter, and why? Pause the video now.

Lucas says, "I could make quieter sounds with the singing bowl by moving the mallet around more gently and not pressing so hard.

This would create smaller vibrations." Aisha says, "I could make louder sounds with the singing bowl by pressing the mallet harder and hitting the bowl harder.

This would create larger vibrations." What about you? Did you think of something else? Pause the video if you'd like to talk about that now.

True or false? Large vibrations create loud sounds.

What do you think? True or false? Yes, that's true.

Large vibrations do great loud sounds.

Can you justify your answer though? Can you give a reason for why you might think that? Here are a couple of suggestions.

A is the larger the vibration, the quieter the sound.

And B is the larger the vibration, the louder the sound.

Which of those do you think is the best explanation for why it's true that large vibrations create loud sounds.

Good idea to pause the video now while you think about that.

Yes, large vibrations create loud sounds and that's because the larger the vibration, the louder the sound is.

Can you explain why Jacob's incorrect? He says, "To make a quiet tapping sound on the table with my hand, I need to hit my hand harder on the table." What do you think? Pause the video if you need to.

Jacob's incorrect because in order to create quieter sounds, we need smaller vibrations.

So Jacob would need to hit his hand more gently on the table to create a quieter sound.

Now, can you complete the table? You need to put a description of how you could make each sound louder or quieter.

So we've got four different sounds: clapping hands, clicking fingers, playing a guitar, and blowing a whistle.

And you have to say how for each one you're gonna make it louder and how for each one you're going to make it quieter.

Pause the video now so that you can do that.

Here are some suggestions.

So clapping hands, to make the sound louder, you clap harder.

To make the sound quieter, clap more softly.

Clicking fingers, to make it louder, you click harder.

To make the sound quieter, you click more softly.

Playing a guitar, to make the sound louder, you pluck harder.

And to make the sound quieter, you pluck more gently.

Blowing a whistle, blow harder to make the sound louder.

And to make it quieter, blow more gently.

I hope you can see the pattern there.

So second part of our lesson now, volume of sounds.

Here's a TV remote control.

Lucas says, "When I'm watching TV, I use the remote control to turn the volume up.

This makes the sound louder.

However, sometimes it needs to be quieter, so I turn the volume down.

Do you know what volume is?" Pause the video if you need to talk about that.

Volume is a measure of how loud or quiet a sound is.

So can I use a remote control to turn the volume up or down on everything to make all sounds louder or quieter? What do you think? Pause the video to talk about this.

So Aisha has an answer for Lucas.

Can you use a remote control to turn the volume down or up on everything to make all sounds louder or quieter? Aisha says, "No.

Remember, it depends on the size of the vibration.

Loud sounds are made by large vibrations and quiet sounds are made by small vibrations.

How would a scientist explain what volume is? You've got three choices.

Here we go.

Is it A, the button on a remote control? B, how loud or quiet a sound is.

Or C, the crowd at a football stadium.

What do you think? Yes, a scientist would explain volume as how loud or quiet a sound is.

Lucas is thinking about places where sounds can be loud.

"I went to watch a football game at a stadium, and it was really loud.

The sound got even louder when someone scored a goal.

I wonder why?" Why do you think the volume of sounds at a football stadium during a match might be loud? Pause the video now so you can have a discussion about this.

Some places such as sports stadiums can get very loud because there are lots of people talking, shouting, singing, and sometimes playing musical instruments.

When a goal is scored, people cheer and shout even louder, which means the volume of the sound increases too.

All of these vibrations add up to make a really loud place.

The volume of sounds can change too.

Lucas says, "The choir at my school are performing a song in assembly.

However, they are very quiet.

What can they do to increase their volume?" Aisha has an answer.

She says, "The choir need to create larger vibrations in their vocal chords by pushing more air through when they sing.

This will increase the volume of sound that they make." What do you think? Pause the video for a moment now so you can have a quick talk about this.

Can you think of any places where the volume of sound is low? Yes, a quiet library.

That would be one place, wouldn't it? It's a quiet place.

And when we speak in a library, we should whisper so that our vocal chords create smaller vibrations.

Smaller vibrations travel through the air to another person's ears so they hear sound at a lower volume.

We can compare the volume of sounds to identify them as loud or quiet.

Lucas, "My baby sister is quiet when she sleeps, but she's loud when she's awake and crying." Aisha, "I wonder if the sound of your baby sister crying has a louder volume than the sound of my brother when he runs around the garden." True or false? The volume of a sound can be changed.

What do you think? Yeah, it's true, it can.

You can change the volume of a sound, but why do you think that? I'd like you to justify your answer.

Have a read of these two suggestions and see which one you think is the best fit.

Answer A, it depends if you have a remote control to change it.

And answer B, it depends on how large or small the vibrations are.

What do you think? Yes, it does depend on how large or small the vibrations are as to whether the volume of a sound can be changed.

Now for task B, I'd like you to make a list of different sounds.

When you've made your list, compare the volume of the sounds and sort them into two groups: loud sounds and quiet sounds.

And then can you put those sounds into order from the lowest volume to the highest volume? You will of course need to pause the video so that you can do that now.

I wonder what sounds you thought of.

Your list might be similar to this: a crowd at a stadium, a car purring, a music concert, a firework, whispering, and a clock ticking.

Compare the volume of the sounds and sort them into two groups, loud sounds and quiet sounds.

Here we are, loud and quiet.

The loud ones are the music concert, the crowd at the stadium, the fireworks.

And the quiet ones: the whispering, the clock ticking, and the cat purring.

Now, sorting them all into order from lowest volume to highest volume.

It might look something like this: The lowest volume, a clock ticking.

A little bit louder, whispering.

Then, a cat purring, a crowd at a stadium, a music concert, and loudest of all, fireworks.

That's the loudest volume of all in the list.

So to sum up our learning today, sounds are made when an object vibrates.

Large vibrations create loud sounds, small vibrations create quiet sounds.

Volume describes how loud or how quiet a sound is and the volume of a sound can be changed.

Well done for working so hard on your learning today.

I'll see you next time.

Bye.