Sunday, February 27, 2011
Saturday, February 26, 2011
Fionúir: Thinking Prompts
Thinking Prompts
Question 1
If you had to design a planetarium, how would you use the properties of light and sound?
Firstly, I would dim the huge spherical ball (planetarium) to show the film on a massive wall! And the film should be 3D to make the show unforgettable for everybody!
Secondly, I would have cool music playing in the background. Especially when there are exciting parts in the show!
Thirdly, I would have a person explaining the show to the audience so everybody can understand what it is all about. Connect the dots!!
Question 2
Why can’t they use flash photography inside?
Firstly, the light of the flash is brighter than the light of the projector so the image would disappear.
Today with our modern cameras a photo would be perhaps possible without a flash light.
Secondly, the flash would disturb the show!
Cheers Fionúir
FIONÙIR, HOW DO WE SEE LIGHT
HOW DO WE SEE LIGHT
Have you ever thought about how we can see light? Or if animals can see the same way as we do?
Well, light is made up of tiny, tiny bits. When the Sun shines, trillions and trillions (1,000,000,000,000) of these light bits fall onto the Earth. These tiny bits or cells are called photons.
Photons
These photons bounce off almost everything and some of them enter our eyes and allow us to see!
Special cells in our eyes tell us what kind of light it is with the help of our brainy brains. These cells are called photoreceptors. They are found at the back of the eye in a layer called the retina. Please see my drawing of the eye. This word is easy to remember. Just think about elderly people in Germany who don’t work anymore, “Rentner”! Let’s connect the dots!!
Picture of the eye
Yellow part is the retina (cones and rods).
How do our photoreceptors work?
There are two types of photoreceptors.
They are cones and rods which are found in the retina. They have these names because of their shapes. They are easy to remember!! Just think about ice-cream cones and fishing rods!!
Diagram of a rod (black and white) and cone (colours)
A cone of yummy ice-cream and cones in your eyes!
A fishing boat and a fishing ROD. In the early morning in the DARK light.
There are three types of cones. And each one lets us see the main colours, red, blue and green.
Just think about lots of different ice-creams; strawberry (red), blueberry (blue), gooseberry (green)!). Cones are more sensitive than rods therefore we can’t see so well at night.
Rods let us see black and white. Just think about out on a fishing boat in the early morning with all the dark colours around.
You may have heard of colour blindness? What is colour blindness? Well, it is a genetic defect. Colour blindness affects 9% of people. Actually men have it more than women!!
Colour blindness
Some animals can see better than others. Some have more photoreceptors than others. You can see this by the animal that they kill. For example, if an animal kills another animal for food and that animal of prey is brightly coloured then the animal that kills can see lots of colours.
Interesting, isn’t it!!
Animal with its animal of prey
Hope you enjoyed reading up on how we can see.
Cheers for now …
Fionúir
Thursday, February 24, 2011
Thinking Prompt Three
Draw a picture, including the earth, sun and moon to demonstrate your understanding of the properties of light.
Thinking Prompt Two
Grade 3 are visiting the Planetarium next week.
Can you explain to them why they can’t use flash photography inside?
Thinking Prompt One following our trip to The Zeiss Großplanetarium
1. If you had to design a planetarium, how would you use the properties of light and sound to ensure that visitors had an enjoyable experience?
Sunday, February 20, 2011
Fionúir: How do we hear sound?
How do we hear sound?
Can you imagine living in a world where you are unable to hear? We wouldn’t be able to hear splendid sounds such as sweet songs, buzzing bees, whispering wind and waves. And we wouldn’t be able to learn as much as we do without our excellent ears. Aren’t we lucky that we can hear? Do you want to know how we hear? If yes, please read on.
How we hear
Sound is a type of energy, just like electricity or light.
Sound is made when air molecules (at least two atoms come together) vibrate and move in a pattern called sound waves.
If you close the door or shout for Mum or Dad, it produces sound waves. Then your brain tells you that you recognise the sound.
Sounds good to you, doesn’t it!?
Picture of sound waves
The human ear
To understand how we hear sound we have to know how the ear works. So I have described how the human ear works. Please read on.
The very first thing that happens is that we hear a sound such as “come and eat your dinner” or “it’s time for school”!
Well, first the sound is reflected by the pinnae (outer ear), then it goes swiftly through the auditory canal (outer ear) and strikes the eardrum (a membrane which looks like a stretched balloon) causing it to vibrate. It then glides on to the tiny stapes (smallest bones in the body) which leads to the circular window. It then continues to travel to the cochlea (looks like a snail!).
After that jolly journey, the sound waves are pushed through the eustachian tube. The auditory nerve sends messages to the brainy brain. The brain tells us what it means and how to react to different sounds.
Most of the ear by the way is inside the head!!! We can only see some of it!!!
Sound travelling through the ear
Please see poster in class.
Dogs barking in their sleep — very cute!
Birds on the trees in spring time singing happily in the foggy, fresh morning.
Classical and pop music, the violin.
Running hot bath.
What sounds do you like?
A girl playing the violin
Some sounds I hate
The sound of mosquitoes buzzing in my ears.
The sound of a lawnmower or vacuum cleaner.
The sound of an electric toothbrush.
The sound of our washing machine peeping at the end.
The sound of a fire brigade siren.
The sound of the alarm clock ringing early in the morning!!
What sounds do you hate?
Alarm clock
Some amazing facts
By the way dolphins have got the best hearing sense of all animals. They can hear 14 times better than we humans.
And what is more children have more sensitive ears than adults. I think
the reason for this that we need to be able to hear dangerous things, e.g a car coming fast towards us, boiling water, falling stones!! Our ears protect us from such possible dangers!!
Fun questions about (?) extraordinary hearing power
Would you like to be able to hear ants or snails communicate?
Why or why not? Please explain your an(ts)swer.
Would you like to be able to hear President Obama talk to his wife and girls? Why or why not?
Would you like to be able to hear Angela Merkel talking to her husband? Why or why not?
Do you think we will be able to do that in the future with groundbreaking technology?
Such as in sci-fi movies today?
TAKE CARE OF YOUR PRECIOUS EARS!
Cheers Fionúir
Fionúir: How do we feel sound waves
How do we feel sound waves
Have you ever thought about how we can feel sound? Have you ever experienced it? When and where?
If you or somebody else hits a drum, the air vibrates inside it. This happens at a cool concert, for example when the delightful drummer hits the drums hard!! Your beautiful body or to be more exact your ventral cavity or other body cavities can vibrate. (Please see picture for more information on the human body). The reason for this is that sound waves need an air medium to travel. As we already know sound travels through air, water and gas.
Body cavities
You can experience this if you are standing close to a stage and if somebody is not standing in front of you, you will feel the sound waves even more as there is nothing to absorb them in front of you. So hide behind the gigantic guy in front of you!
The song called “I wanna feel the music” is a good example of people singing about
trying to feel the music because they want to have fun! Please check it out on YouTube!!
Enjoy!
Sometimes even the ground where you are standing on or the surrounding walls can vibrate.
I noticed this when I was at the Taschenlampen concert last year with my friend, Bianca.
And I also noticed this at Lino’s mother’s birthday party when the band played out their music wonderfully.
A drummer in action
Sound waves can KILL!!!
Have you ever thought about why a bomb can actually kill people, for instance? An explosion can squash you like a horse can squash a poor little innocent fly! How terrible!!
A bomb is made up of heat, flames, shrapnel (pieces of sharp metal) and a pressure wave. The heat and flames and shrapnel might not kill you, but the loud B A N G just might!! The over-pressure can crush your internal organs (e.g heart, lungs, liver) causing you to bleed to death!! Sorry for these rather unpleasant details!! But it is fact!
Sound waves
The police and military have thought about using sound weapons where the concentrated pressure makes you feel nauseous (feel as if you have to vomit) and all confused. That means the criminal cannot run away and the police can arrest him/her. However, this is illegal at the moment.
The next time you are at a concert, or maybe just waiting impatiently for the train to arrive, or listening to burly guys making loud noises on a building site, you now know that your cavities might be vibrating. The sound waves like your air cavities but not the cavities in your teeth! ;=)))
Look after all your cavities by not exposing yourself too much to loud noise and by brushing and flossing your teeth as often as possible.
Goodbye for now with that enlightening message.
Cheers Fionúir
Friday, February 18, 2011
Ariane - Aurora Borealis And Aurora Australis
Aurora Borealis
and
Aurora Australis.
They are visible from
Alaska, Russia, Norway and Canada on the northern hemisphere and from
Antarctica, South America, Australia and South Asia
on the southern hemisphere.
Only in recent times scientists have developed accurate theories on the origins of polar lights.
The powerful Sun wind interacts with the Earth´s magnetic field. Particles from the Sun collide with the atmosphere and cause the appearance of light at the poles.
Sometimes the Sun wind causes real magnetic storms. These are powerful enough to knock out a power station on Earth or disrupt the function of satellites within the atmosphere. During a solar storm, the Taxi drivers in Sweden could hear the Taxi drivers over the mobile phones in Hamburg!
Auroras can be spotted on other planets with magnetic fields and atmosphere. For example, polar lights have been observed on Jupiter and Saturn.
The Aurora Borealis is like natural fireworks. It has beautiful colours like green, pink, brownish-red, yellow, purple or pure blue.
In the past people searched for answers for the appearance polar lights.
The Makah Indian tribes thought the Aurora was a dwarves´ fire. The dwarves were supposed to hunt whales and gather around the polar fire.
Please look at the photographs very carefully. Maybe you have seen these lights in films before.
Please post a comment and write about similar lights you may have seen in other movies.
Sunday, February 13, 2011
Fionúir: What is sound?
What is sound
People hear sound all day long. But not when you are sleeping!! We communicate with sound and rely on it. Sounds can warn us or tell us if something is dangerous or not. Especially animals rely on sound such as dolphins which mostly swim in the deep blue ocean. Dolphins can hear sounds that come from far, far away.
If you would like to draw a picture of sound
it could look like this …
One person talking to the other and one listening. The semicircular (half a circle) lines in the air represent sound waves like ripples in a pond!
Sound needs air, gas, or water. This is known as a medium.
Did you know that sound can’t travel through outer space because the vacuum doesn’t contain any medium to carry sound.
Bad news for Star War fans!!
...
Fionúir: How do we see sound waves?
How do we see sound waves?
Well, we can see sound waves but we don’t always know this! With this clever experiment you can … with this special creation!
You will need the following items to demonstrate it
- an empty tin with both ends cut off
- a balloon
- scissors
- some tape
- a piece of foil
- a flashlight
How you make it
Firstly, you cut off the fat end of the balloon.
You stretch the fat end of the balloon over the tin, which should look like a drum. Then you place the foil right in the middle of the balloon. To hold it you stick the tape on the back of the foil.
It looks like this
How it works
The open-end is for singing or speaking into, whatever
you choose to do. It works best if you sing a song such as
Mommy made me mash my M&Ms, oh no!!!!
Dim the lights or turn them off. Put on the flashlight and shine it on the balloon. Sing into the tin and the sound waves hit the rubber balloon and it vibrates …!!!!
Now you can see clearly the vibrations!
IMPORTANT
You should try it out in a dim or very dark room as you can see it much better.
I hope you enjoyed reading about this experiment! Perhaps we can do it in class together with my simple creation.
Mr Shillitoe and class, what do you think?
Thank you for taking interest in my idea to show you all how we can
see sound waves!!
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