Pages

27 Mar 2013

Big Questions

There is a great book titled: Big Questions from Little People: and Simple Answers from Great Minds which you can use in your lesson. The book consists of basic questions asked by children and answered by scientists and philosophers, e.g. "Why we have dreams", "Why we can't tickle ourselves" or "Why we're all made of stardust?".

You can put Sts into groups and give each group different set of 3 questions (together with answers). Give each group time to read and understand them. Tell each group that they are the experts and have to share their knowledge with other groups. So they have to ask their mates the questions and make sure their friends get the correct answer.

If you don't have the book, here are some of the questions you can use:

  • WHAT ARE ATOMS?
Atoms are the building blocks out of which everything is made: you, me, trees, even the air we breathe. You cannot see atoms because they are very small. It would take ten million laid end to end to stretch across the dot of the exclamation mark at the end of this sentence! But if you could see an atom, you would notice something very odd indeed. They are not made of much at all. In fact, they are pretty much all empty space. At the centre of an atom is a tiny speck of matter called a nucleus. Circling it, like planets around the Sun, are even tinier specks of matter known as electrons. But in between the nucleus and the electrons is a lot of empty space. It means that you and I – since we are made of atoms – are mostly empty space. In fact, there is so much empty space inside atoms that if you were to squeeze out all the empty space from all the atoms in all the people in the world, they would fit in the volume of a sugar cube. Imagine. The whole human race squeezed down to the size of a sugar cube. Mind you, it would be a very, very heavy sugar cube!One more thing about atoms. They come in ninety-two different types (plus a few kinds that do not exist in nature but that scientists have made). And, just like if you put together different combinations of Lego bricks, you can make a house or a dog or a boat, atoms go together in different combinations to make a rose or a tree or a newborn baby. All of us are combinations of atoms. We are all different from each other because we are all different combinations of atoms.
  • WHERE DOES WIND COME FROM?
Wind is just air moving from one place to another.The source of the wind, as of so many things, is the Sun. As the Sun warms the Earth each day, it doesn’t heat everywhere equally because some places catch the sunlight better than others. The place that catches it best is the Earth’s waist, the equator, which is why places near the equator are hottest: the jungles and deserts and tropical islands. The places that catch the sunlight least well are the edges, the poles. This is why they are all snow and ice, and unless you’re a penguin or a polar bear there’s not much point being there.Now, when air warms up, it rises. And as it rises – this is the important bit – something has to take its place: more air that’s not so warm. As the warmed air rises, cooler air moves in to take its place, and – Presto! – that moving air is WIND.Hurricanes and gales happen when the air is moving fast (because more air has risen, making room for lots more to rush in). Gentle breezes are when it’s moving slowly, because less air has risen.The atmosphere – the bubble of air around the Earth that we breathe – is warming and cooling and moving and mixing all the time, which is why our weather changes. If it’s all down to the Sun, how come the wind also blows at night? Because, of course, though it’s night for you, it isn’t night everywhere. Somewhere on Earth the Sun is always shining, warming, making the air move.
So there you are. As for the wind your dad produces? You know as well as we do: that’s because he eats too many baked beans.

  • WHY DO MONKEYS LIKE BANANAS?
Monkeys eat lots of different foods. They eat fruit, vegetables, seeds, leaves and even insects. But they love bananas because they’re very sweet and tasty. Just like us humans, monkeys enjoy eating yummy foods, and bananas are one of their favourite sweet treats. Also, monkeys usually want to eat as quickly as possible, so that other monkeys don’t take their food. (They can be quite naughty and will often steal each other’s food.) Bananas are soft and squashy, so monkeys can eat them fast. Different monkeys have different ways of eating bananas. The very greedy ones eat the bananas whole, skin and all. Others will peel off the skin and only eat the soft fruit inside. Some monkeys are not very good at peeling the strong skin, and instead roll the banana really hard until the soft part squeezes out of the ends. This is a clever but very messy way of eating bananas! Monkeys use up lots of energy climbing, running and swinging in trees. Bananas contain something called fructose – it’s like sugar and gives the monkeys the energy they need to do all these things.
  • WHY CAN’T I TICKLE MYSELF?
It’s puzzling, isn’t it? No matter where you try to tickle yourself, even on the soles of your feet or under your arms, you just can’t. To understand why, you need to know more about how your brain works. One of its main tasks is to try to make good guesses about what’s going to happen next. While you’re busy getting on with your life, walking downstairs or eating your breakfast, parts of your brain are always trying to predict the future. Remember when you first learned how to ride a bicycle? At first, it took a lot of concentration to keep the handlebars steady and push the pedals. But after a while, cycling became easy. Now you’re not aware of the movements you make to keep the bike going. From experience, your brain knows exactly what to expect so your body rides the bike automatically. Your brain is predicting all the movements you need to make. You only have to think consciously about cycling if something changes – like if there’s a strong wind or you get a flat tyre. When something unexpected happens like this, your brain is forced to change its predictions about what will happen next. If it does its job well, you’ll adjust to the strong wind, leaning your body so you don’t fall. Why is it so important for our brains to predict what will happen next? It helps us make fewer mistakes and can even save our lives. For example, when a chief fireman sees a fire, he immediately makes decisions about how best to position his men. His past experiences help him foresee what might happen and choose the best plan for fighting the blaze. His brain can instantly predict how different plans would work out, and he can rule out any bad or dangerous plans without putting his men at risk in real life. So how does all this answer your question about tickling? Because your brain is always predicting your own actions, and how your body will feel as a result, you cannot tickle yourself. Other people can tickle you because they can surprise you. You can’t predict what their tickling actions will be. And this knowledge leads to an interesting truth: if you build a machine that allows you to move a feather, but the feather moves only after a delay of a second, then you can tickle yourself. The results of your own actions will now surprise you.
  • CAN A BEE STING A BEE?
Yes it can. There are about twenty thousand species of bee in the world, but let’s look at honey bees and bumble bees. Although some species are stingless, female bees typically have a sting to defend their colony against enemies that might steal their honey or even eat the bees themselves. Male bees do not have a sting and do nothing in the colony except for a few of them that will mate with the queen bee. Honey bees will attack worker bees from other colonies if they try to enter, but a queen honey bee will only sting and kill other rival queens. A newly emerged queen will search the colony for cells where other queens are developing and when she finds them she will sting and kill them. Bumble bees will attack workers from other colonies, too. They can sting them to death but usually they bite them and drive them out. In some cases the intruder may be able to hide inside the nest and may be accepted as a new member of the colony. Bumble bees also fight and sting each other within the nest. The reason is complicated but is basically a way of reducing the numbers of males the colony produces. Why do they need to reduce the number of males? Because worker bumble bees can lay unfertilised eggs, which develop into males, but what the colony really needs are worker females. The worker bees of some honey bee species have a special killing technique for large predators such as giant hornets. They form a ball around them and as the hundreds of bees vibrate their wing muscles the temperature and carbon dioxide levels inside the ball of bees increase and kill the hornet.
  • HOW DO THE BUBBLES GET INTO FIZZY DRINKS?
You know how you can dissolve things like sugar in water? What happens is, all the little bits that make up the sugar granules separate from each other and spread out. These little bits are called molecules and they’re so small you can’t see them. That’s why the granules seem to just disappear! Well, you can do the same thing with bubbles of gas. But to get bubbles to dissolve you have to squeeze them really hard. That is to say, you have to apply loads of pressure. Which is why when you open a fizzy drink you hear a hissing sound. That’s the pressure being released. And what happens when you release the pressure? All those little dissolved molecules come back together and form bubbles again. If you drink really quickly after opening a can, loads of the bubbles will grow in your stomach and you can do massive burps.
  • WHY IS THE SKY BLUE?
Guess what? The sky is not blue. At least, there’s no blue stuff, no blue pigment, in the sky. It’s a trick of the eye. Up there, and all around us, are gases of different kinds, such as oxygen, nitrogen and carbon dioxide. There’s also dust, water vapour, spores and even tiny airborne animals. When sunlight hits something, it gets reflected. Big objects, such as the Moon, reflect the light very well. Moondust is dark, but so reflective that the Moon shines brightly in the night sky. But a tiny gas molecule is too small to act as a mirror. Instead, it absorbs light, and then sends that light bouncing back out again in a random direction. In other words, every molecule in the air is a tiny, flickering light source. Imagine for a moment that light was sound. Sunlight is not just one note of a certain pitch played on one instrument; it is a vast orchestra playing every imaginable pitch at every imaginable volume! We see just some of this music. Our eyes perceive different pitches of light as colours: violet, blue, green, yellow, orange, red and purple. Air molecules absorb blue light very easily, and they send it bouncing away just as easily. This is why blue light is scattered all around the sky, and why it reaches our eyes from all directions. Everywhere we look, we are bombarded with blue light. That is why the whole sky looks blue. The other colours aren’t nearly so easily scattered by the Earth’s atmosphere, and they come to us in a more or less straight line. DON’T look directly at the Sun, because if you do, every colour there (aside from a little sky blue) will be hitting the back of your eye at the same time. That much light really can damage your eyes. If Mars had more gas in its atmosphere, it too would have a blue sky. As it is, there isn’t enough gas for this scattering effect to work. If you could stand on the surface of Mars and look up, you’d see the sky there is the white of raw sunlight, tinted beige by dust. Towards the Earth’s poles, the Sun sits low in the sky and sunlight has more atmosphere to pass through before it reaches the ground. Here the sky is especially blue.
  • DO NUMBERS GO ON FOREVER?
Here’s one of my favourite mathematical jokes to help answer this question:
A maths teacher asks the class: ‘What’s the biggest number?’
One of the kids quickly puts up his hand. ‘A trillion,’ he announces.
‘What about a trillion and one?’ the teacher responds.
‘Well, I was close,’ the child replies triumphantly.
The reason this is funny (of course it always kills a joke to have to explain why it’s funny) is that the child thinks the teacher’s answer of ‘a trillion and one’ is actually the biggest number that exists. In fact, the teacher is giving an answer to the question ‘Do numbers go on forever?’
If numbers didn’t go on forever, it would mean there had to be a biggest number. But if there was a biggest number, I could play the same trick as the teacher. I could add one to that number, and now I’ve got an even bigger number. The numbers never run out. They do go on forever.

  • WHO INVENTED CHOCOLATE?
Chocolate as we know it, in bar form, was the invention of Mr Fry of London in 1847, but chocolate has been used for thousands of years. The Mayans and the Incas, in Central and South America, used a kind of chocolate drink in their religious ceremonies and the habit was brought over to Europe by the early explorers.Christopher Columbus is said to have brought the first cocoa beans back to Europe in approximately 1503 but no one was sure what to do with them. A few years later, Spanish conquistador Hernán Cortés discovered the ‘New World’ and when he returned to Spain from Mexico in 1528, he loaded his galleons with cocoa beans and the equipment to make chocolate to drink. It took over a hundred years, however, before the custom of drinking chocolate spread across Europe to England. After that, drinking chocolate became very fashionable among the wealthy, and was even once denounced by the Pope because it made people greedy!
  • WHY DO I GET BORED?
You know what elephants are like. They are big and grey and very strong. And they have very, very long grey, hairy noses called trunks. They can pick things up with their long noses and they can suck things up with them as well. I don’t think I would ever get bored if I had my own trunk. I’d use mine to suck up water and spray my friends for fun. But elephants do get bored. And when they get bored it makes them grumpy. They sway from side to side, thumping around on their great big legs, and they toss their trunks all over the place. How do you cure elephants of boredom? You play them some music. They like serious, old-fashioned music with lots of violins. That doesn’t surprise me, because I’ve always thought elephants were very old-fashioned things. They live for a long time and become very old. Do you like the sort of music that elephants do? I’ll bet you don’t. You’re probably more like a chimpanzee. Some scientists at Belfast Zoo in Northern Ireland have discovered that chimps get over being bored and grumpy if they listen to rock ’n’ roll.
But why do elephants get so bored that they need to listen to music? They get bored if they’re in small zoos and there isn’t enough to do. They get bored if they can’t wander about with their friends, and if they know exactly what’s coming up next: hay for breakfast, hay for lunch, hay for dinner. Same bed, same old cage, same old friends. You get bored the same way. There’s not enough to do. Your friends are somewhere else. You have to be still and quiet and stay indoors when you really want to play outside. Being bored is your body telling you to do something different, so you don’t get sad or grumpy. You need to get out with your friends and family, and find new and exciting things to do. Next time you feel bored, why not try the elephants’ cure? Put on some music and swing your trunk. Or be a monkey, and listen to some rock ’n’ roll!

No comments:

Post a Comment