Science, Curiosity and Life
Science Wows is all about sparking children’s natural interests in Science!
It is learning while having fun!Whatever the event, whatever the venue it is Hands-on Science for children. Party entertainment, school visits, fun days, corporate events …. there are even local science camps during school holidays.
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If you can’t explain it to a six year old, you don’t understand it yourself”
That is (apparently) one of Einstein’s many quotes. It took me a while to realise just how true these words are, but once I did I was able to marry a love of writing with a love of science. I discovered that once I broke things down to their most simple components
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Dr. How’s Science Wows was set up by me (Naomi) in 2011. My background is biochemistry with a PhD in Molecular Biology; I have worked in the Medical Diagnostic Industry and lectured at third level colleges but the crux of what I do lies in many years working with children; from two to 20 they all have one thing in common…. curiosity!
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My first Mystery Monday on the new blog site and I have decided to make it a fun one ;0)
So here is this week’s Mystery Creature (on the left of picture below)… it is a bear (obviously) but what kind of bear???
(Or just check out the end of week reveal here)
It has been exactly a month since my last blog and I have some serious withdrawal symptoms at this stage. I would like to say I was on a holiday, that I am back now, tanned and refreshed, batteries completely recharged, but no, that’s just wishful thinking! I was actually moving house – of a sort anyway! I decided that it was silly to have a website in one place and a blog in another so it was time to amalgamate the two and rather than take the easy option, I decided both needed to move! Hence I spent the time creating a new place for both to live…. and here it is!
So come in, sit down and pull up a cosy chair… I’ll put the kettle on!
They say that moving house is one of the most stressful of life events and now I can testify that a virtual move is almost as bad! First there was the hours of trawling through themes (I eventually chose this one, and would recommend it!). Then deciding what I want to go where – and working out how to fit that into the theme. All was going well until I decided to migrate the blog to it’s new site! The migration bit is easy, but then I also wanted to transfer over all links, google rankings etc. That is when it all went a little pear shaped… and I managed to crash the whole site late last Thursday night… Yup that was a cheery moment!
All’s well that ends well though, and I have a few people I really must thank for that …. firstly, the man who designed the theme, Rohit Tripathi, who came to the rescue after just one e-mail! I also have to thank James from webhost.ie for being so helpful and patient with the never ending barrage of questions; and a really big thanks to all my fellow Irish Parenting Bloggers for all their tips and advice and in particular their support and encouragement when it all went wrong!
As you can see there is still plenty of “housework” and “decorating” to be done but I’m glad to be back! My regular Science related blogs should resume shortly so let me know if you have any new questions for me and I’d love to hear what you think of my new abode!
I love it when I get questions on the blog, that’s what it is all about! Today some junior scientists (who can sometimes be found here) wanted to know….
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| photo credit: philografy via photopin cc |
A very good question, do you know the answer?
Well first up, some electrical wires are insulated so that even if we touched them we would be safe (but I am not suggesting that you try that!) Other wires rely on air as their insulation so they pose the most risk to anyone touching off them.
For electricity to flow tiny particles called electrons need to move! When we use a battery in a toy it has a plus side and a minus side and electrons travel from the minus to the plus creating a flow of electricity. These electrons need something to move through… we call the thing they move through a conductor. A good conductor is something that allows electrons to flow easily through it; electrons cannot pass so easily through a bad conductor.
Electrical wires are often made of copper which is a very good conductor. The electrons are very happy because they can move easily through it. A bird’s body is not such a good conductor so the electrons would rather stay flowing through the copper wires than flow through the bird. So the birds remain quite safe.
Here is a good way to think of it…. which would you find easier to swim through… nice clear water or thick oozy mud? If you want to move quickly the water is a lot easier to move through, isn’t it? Just like the electrons moving through the good conductor.
So while the bird is sitting on a wire high up in the air the electrons choose to keep on their path through the copper wires and not pass through the birds at all. But what needs to change for the birds to get an electric shock? We already spoke about the fact that electrons like to pass through good conductors rather than bad conductors but electrons also like to go from places of high voltage to places of lower voltage. Voltage is really just electrical pressure, so electrons like to move from a place where the electrical pressure is high to a place where it is low.
While the bird stands on the one wire there is very little difference in voltage BUT if it was to touch off a second wire of a different voltage then it will find itself in trouble. The electrons will flow from the wire of the highest voltage to the wire of the lowest voltage, passing through the bird. This means the poor bird will get a very big electric shock. Also there is no voltage on the ground so if the bird was touching the ground while touching the wire them the electrons would flow from the wire (high voltage), through the bird and into the ground (no voltage). Not a good situation for the bird at all.
In theory, if we were to hang off an electrical wire in mid air, we too would be unaffected, just like the bird. However, if we are standing on the ground when we touch a wire the electricity will pass through us to reach the ground and we will get an electric shock. NOT A GOOD IDEA!
I hope you liked this explanation, if you have any questions or comments please leave them in the comments below… I always love to hear from you! And remember… if you or someone in your family has a question they would like answered here on the blog please do let me know!
Hubby was up and gone early on Saturday morning while the rest of the family slept on to a more respectable hour. I was up a while before I spotted the bag by the front door. I thought it might be a forgotten birthday present for my daughter and peeped in to have a look, I got a bit of a fright when I saw something dark and furry inside!
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| Common brushtail possum; photo credit JJ Harrison via Wiki Commons |
Current estimates suggest that there are 30 to 40 million possums in New Zealand (compared with a human population of 4.5 million).
The New Zealand possum population can eat through 21,000 tonnes (approx 180,000,000 kilos) of leaves, fruit and berries in one night!
So that is the story behind my possum pelt, it was actually given to my husband from a friend who has recently returned from New Zealand, where he worked on one of the possum culling programs. So we have learnt a little about the possum in New Zealand thanks to this gift but I still have no ideas of what to do with it. Have you any suggestions? If so please do let me know in the comments below!
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| Our new possum pelt… any suggestions what we can make with it? |
Well it’s been a great week and thanks to all who participated in the competition, there has been a great response! All names were given a number and I used a random number generator to keep everything fair.
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| All ready for a new home! |
So the four lucky winners are….
I will be in contact with each of you to find out the mailing address.
I am sure that recipients will really enjoy their kits …. just remember to let the children have a go too ;0)
I would like to thank all of you that liked, commented and shared throughout the week, the support and interaction was really heart warming. I will definitely run another giveaway during the year!
To round things off, here is a link to a previous blog post all about magnets, with two experiments to try… so even without the kits you can all have some magnet fun!
I am getting lots of questions from three and four year old children lately which I love, it seems they all hold a communal fascination with slugs and snails and the working of both.
I hear that a little lady who can often be found here wants to know….” Do slugs have eyes?” and two little ladies that can be found here want to know if they have ears and noses too. My own son asked me the other night as I put him to bed… “What are slugs made of?”
I thought it only fitting, among all this slimy fascination to dedicate the whole week to all things slug and snail like. I have been sharing some facts and photos on my face book page!
So in today’s blog I will try to answer some of these Junior Scientists’ questions and hopefully add a few more facts to further inspire them.
Slugs (and snails) do have eyes, two of them, they sit on top of two tentacles (called eye stalks) on the top of their heads! They do not see colour and form as well as we do but they can still make out shades of light and dark. Although the eyes are well developed they do not have a complex method of focus.
They can retract their eye tentacles to protect their eyes from potentially harmful touch.
Slugs and snails do not have ears and a nose like we do but they can still smell and they can detect some sounds through vibration. They use either their eye tentacles or two smaller tentacles below the eye tentacles for these senses. The lower tentacles are also important for sensing taste and touch.
If a snail or slug looses any of these tentacles they can regrow it!
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| Slug photo credit: [martin] via photopin cc ; Snail photo credit: sea turtle via photopin cc |
Slugs and snails are effectively the same except that snails have an obvious shell and slugs do not. Some slug species may have a small vestigial shell or an internalised shell but most have no shell at all. Slugs do not require calcium in their diet whereas snails do in order to maintain a healthy shell.
Both slugs and snails belong to a group of animals called mollusks. In fact they are very successful creature, being listed as the second most abundant species on Earth. Found in almost all habitats and temperatures, they are most affected by harsh winds and very dry conditions.
Slugs (and snails) are mostly made up of water! Their soft bodies are covered in a thick sticky mucous. They breath into a single lung through a pore on the skin and have a mouth part under the tentacles. They “eat” their food by extending a tongue like organ called a radula from their moth. The radula is very rough as it is covered in tiny tooth like protrusions. The radula breaks up the food by rubbing it.
Photo Credit: Betty Kehoe of aislingdesigns.ie
Although slugs and snails do not have complex brains they are still able to analyse and respond to stimuli through a series of nerves bundles.
Most land slugs and snails are noctural but they will often come out after rain as they prefer damp conditions. Not only do these conditions help them to move around but they also stop them from suffering dehydration.
Slugs and snails have no legs for walking, instead their bodies ripple and slide along on a film of slime that they make themselves. They have a “foot” on the underside of their bodies that rhythmically contracts and relaxes a series of muscles that provide the rippling effect. They secrete a thin light mucous to reduce the friction between the foot and the surface, allowing them to glide along. An efficient but slow method of getting from place to place.
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| photo credit: marianbijlenga via photopin cc |
Slugs and snails also produce a thicker mucous that covers the whole body, acting like a thin armour that protects the slug from severe weather as well as keeping dirt and harmful germs out of the body.
Despite their bad reputation not all slugs and snails are only out to eat your prize cabbages! Many eat dried organic matter such as dead plant parts and leaves, thus contributing positively to the ecosystem and returning all their nutrients to the soil. Some are carnivores or omnivores, eating small insects or even other small slugs and snails.
If you want to find out more fun facts about slugs and snails, such as “How strong are they?” and “Who would win in a race – a slug or a snail?” then check out the Facebook page for daily posts!
The kit is by 4M and contains all the equipment and instructions you need for ten fun experiments and games including a fishing game, magnetic racing car, build a magnet man and many more.
I have used this kit to teach my four year old all about magnets and often take it out for all three children to play with on a rainy day.
So if you would like to be in with a chance to win one of four of these great kits just share this post on Facebook, twitter, pinterest or G+ and leave me a comment below; (You can also enter the competition through my Facebook page by liking and commenting).
The competition runs for a week and I will announce the four lucky winners next Friday 17th January;
Disclaimer: This post is not sponsored in any way, the kits have been purchased by me and I have not been paid to review these kits.
Does sound travel faster in warm or cold air?
I was asked this by the principal of a school I was visiting during Science Week last year. I gave him the short answer… it travels faster through warm air.
Technically that is correct.. it does travel faster through warm air… the molecules in the warm air are more “excited” and will vibrate more easily. Sound needs vibration in order to work so the sound is carried more easily through the air with the more excited molecules than through air with more “still” molecules (cold air).
A good way to think of it is to imagine a line of dominoes. The air molecules are the dominoes.
Sound makes air molecules around the source vibrate and hit off the next molecule which vibrates and hits of the next (just like the dominoes hitting off each other) and the chain keeps going until the sound reaches your ear… and then the vibrations get carried on to your middle and inner ear until they are changed to electrical pulses that are sent to the brain!
And there was me thinking I was keeping this simple… back to the dominoes… just keep thinking of it like a string of dominoes. Actually that is not quite true…. for the domino model to really mimic the movement of sound you have to arrange the dominoes in concentric circles, not in straight lines. Sound travels outwards from the source in all directions.
So there you have it sound does travel faster in warm air BUT it may appear to travel farther in cold air.
This is how that works…
…if the air close to the ground is colder than the air above it then sound waves travelling upwards will be bent downwards. This is called Refraction. These refracted sound waves can act to amplify the sound to someone standing far away.
I expected the first morning back to school after the Christmas break to reduce some of us to tears but to be honest, it went fairly well considering! The tears, when they did come, were not over having to get up early, get dressed and get out the door in time. The tears came from the nine year old when I asked her to wear her outdoor runners to school. Turns out the laces keep opening and she was getting a bit of a slagging from her peers for not being able to tie them. So after a rush of parental guilt and a quick change of footwear she got out the door with tears dried up and a smile on her face.
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| photo credit: chriѕ chan via photopin cc |
It did get me thinking though… the guilt obviously… I mean in my day we could all tie our laces by about five years old. How had I let my poor daughter get to nine without this basic life skill? It seems this is a common occurrence in our modern society. We had no choice as children though as most of our shoes had buckles or laces.To be honest I had thought that my daughter had mastered this skill a year or two ago but nowadays most shoes don’t have laces so she never got to keep practicing. When she returned from school we did sit down to learn it and it turns out she was just lacking confidence, not ability and had it remastered within a minute or two… it left her feeling very pleased with herself and me feeling a little less guilty!
So how many times do we need to repeat a task, like tying our shoe laces, in order for it to be learned for life? And what level of dexterity is required? Is there a right and wrong way and does how you tie your laces effect the performance of the shoe? I just had to go find out and you might be surprised by what I found… I was!
Tying our shoes laces is a Fine Motor Skill, requiring the use of small muscle movement and we need to program this movement into the brain before it becomes an accomplished skill. The part of the brain most involved with this activity is the motor cortex. We can begin to learn fine motor skill by observation but it is through practice that we really “hard wire” the information and retail the skill.
Tying shoe laces is not as easy as we may thing and when I researched the topic a little I found out that many recommend waiting until your child is a least six before teaching them this skill. As well as the complex dexterity required children also need to be able to remember and follow a number of steps as well as being efficient in Bilateral Motor Coordination (using both hands at the same time).
While I was researching this topic I found out that I have been tying my laces the wrong way for years and never knew. Check out this video to see if you have been too. If you need even more science on the subject here is another link.
Imagine, all this time I thought I had that one sussed! Now my feelings of parental guilt have turned to feelings of adult ineptitude… and all because of a pair of shoe laces!
Not only is there a correct way to tie the bow of your lace but research has also been carried out on the effects of different shoe lacing patterns on the biomechanics of running shoes. Now we have no more excuses for laces that come undone or aching feet and limbs!
If you are thinking of teaching your child this life skill here are a few tips I have picked up…
You may be glad to know that my daughter got up this morning and deliberately chose the laced shoes herself arriving up for breakfast fully laced and very proud. That’s my girl!
Did you guess the name of this week’s Mystery Creature? It is a recently discovered sea slug named Tritonia Khaleesi. The scientist that discovered it must have been big fans of The Game of Thrones as they thought the pale markings on the back of the sea slug resembled the braided tresses of the character Daenerys Targaryen, often called by her official title of Khaleesi (Princess) in the series.
This new sea slug really caught my interest when I saw its name as I had just Game of Thrones over Christmas.
Do you see any similarities?
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| Image credit: HBO |
The sea slug was found off the Northeastern coast of Brazil. At just 12mm in length it is one of the smallest known sea slugs.