craigwend
Grimpeur des terrains plats
My favourite is q 7...
(edited version)
1. WHY DON'T ALL FISH DIE WHEN LIGHTNING HITS THE SEA?
Expert's answer from the Institute of Physics: "Fortunately, only very unlucky fish ever get killed by lightning. Air is an electrical insulator, which means that electricity cannot normally flow through it. During a lightning storm, the very large voltage between the cloud and the ground causes the air in between to break down along a very narrow path, and all the electricity passes down this path (called the lightning streak). When someone is killed by lightning, he or she has unluckily become part of the path and the enormous current that passes through the body kills him or her. Sea water, on the other hand, conducts electricity so as soon as the current enters it, it spreads out in all directions and any fish in the way would probably only experience a small current passing through it, so sparing it from death. Only fish very near the water's surface would be killed. A fish as little as a foot below the surface would probably be quite safe."
2. HOW MUCH DOES THE SKY WEIGH?
Expert answer from the Science and Technology Facilities Council's Space Science and Technology Department: "If you want the total weight then it's about one millionth of the mass of the Earth, which is the equivalent of 570,000,000,000,000 adult Indian elephants."
3. WHY CAN'T PEOPLE LEAVE OTHER PEOPLE ALONE?
Philospher Mark Vernon suggests this approach. "Human beings are social animals, like ants; we thrive when we live well together, in families and communities. But unlike ants who just get on, humans make friends and enemies. It's then that we can't let others be.
"Or, a really short answer: As we make friends, so we make enemies."
4. WHY AREN'T BIRDS ELECTROCUTED ON WIRES?
Expert answer from the Space Science and Technology Dept: "Being electrocuted involves a current passing through you. For a bird to be electrocuted it would need to touch two wires at different voltages, or one wire and the grounded structure of the pylon, at the same time. If they did this there would be a current flow and the bird would be likely to be electrocuted. However this is very unlikely to happen and electricity authorities also give considerable thought to the design of their pylons to minimise the chance of birds being electrocuted."
5. WHAT IS TIME?
Expert answer from the Space Science and Technology Dept: "This is a difficult question to answer. Some scientists may call time the flow of cause and effect. A more detailed explanation could be, according to the Theory of General Relativity, that time is the path which an object will take through a four dimensional universe when left to itself. In such a universe, the four dimensions are indistinguishablefrom one another: they are not three dimensions of space and one of time. Such an approach can be used to explain the time dilation of special relativity - that time slows down as one approaches the speed of light in a vacuum - but this is not an argument that is accepted by all scientists."
6. WHY IS THE MOON SOMETIMES OUT IN THE DAY, TOO?
Expert answer from the Institute of Physics: "When the Moon revolves round the Earth, half of the time it is on the same side of the Earth as the Sun, and the rest of the time, they are on opposite sides. When the Moon and Sun are on the same side, the Moon is 'up' during the day. When they are on the opposite sides, the Moon is 'up' during the night. So surprise, surprise, the Moon is up during the day as often as it is up at night."
7. WHY DID GOD LET MY KITTEN DIE?
Mark Vernon's answer: "No-one knows for sure, though many people have tried to find an answer. What we do know is that when people and pets die, we care for them all the more, which says a lot about why compassion is so important."
Or, a really short answer: "No-one knows, but you know you care."
8. WHY DO I LIKE PINK?
Mark Vernon says:"Favourite colours unconsciously remind us of things that we find pleasurable or valuable. Pink is often associated with fun, like pink sweets; or the feminine, like pink clothes. Sweets are pleasant; the feminine is valuable."
His really short answer? "Pink reminds you of other things you like."
And psychologist Dr Stephen Briers, of the Science: So what? So everything campaign, says: "Traditionally it is thought girls like pink more than boys do. Scientists have found there may be a biological basis for why girls prefer pink, or at least more reddish colours than boys. Research has found that although more people prefer blue, women tend to prefer pinker shades. Some biologists say that this is because in Stone Age times a woman's role was to pick out reddish-coloured fruit, so they became more sensitive to reddish colours. Another scientist has suggested females may also prefer reddish colours because they need to be more able to spot when their children are ill with a fever (and therefore have a more reddish tone to their faces), or because changes in skin colour can let you know what a person is feeling and help females to read emotions better."
9. WHY IS WATER WET?
Expert answer from Stephanie Bell, of the National Science and Engineering Week: "There are two answers to this question: One answer is about what makes liquids stick to surfaces and 'wet' them - which is to do with forces between molecules. Water molecules are 'polar' - the arrangement of electrons means that electrical charge isn't evenly spread - and this makes water particularly attracted (electrically) to many surfaces. It also causes water to have lots of other interesting properties.
"But why does water feel wet? This is for a completely different reason. When you have water on your clothes or skin, it normally evaporates into the surrounding air. Evaporation produces cooling, because it takes energy. The feeling of wetness is actually coldness. You can test this by comparing water with another liquid - cooking oil - which doesn't evaporate so freely. Fill two small cups (egg-cups are ideal) - one with water, and the other with cooking oil. (Young children should ask an adult to help.) Let both liquids come to room temperature for a day, or overnight. Dip one index finger in each liquid, lift them out, and then observe for a few minutes."
10. WHY DOES MY BEST FRIEND HAVE TWO DADS?
Mark Vernon says: "People meet and fall in love. It's an old story. Ideally, their love grows, and they may raise children, as an expression of that love. Usually, a man and a woman fall in love and have kids. But it can be two women, or men."
And his really short answer: "Two men, and two women, can fall in love too."
(edited version)
1. WHY DON'T ALL FISH DIE WHEN LIGHTNING HITS THE SEA?
Expert's answer from the Institute of Physics: "Fortunately, only very unlucky fish ever get killed by lightning. Air is an electrical insulator, which means that electricity cannot normally flow through it. During a lightning storm, the very large voltage between the cloud and the ground causes the air in between to break down along a very narrow path, and all the electricity passes down this path (called the lightning streak). When someone is killed by lightning, he or she has unluckily become part of the path and the enormous current that passes through the body kills him or her. Sea water, on the other hand, conducts electricity so as soon as the current enters it, it spreads out in all directions and any fish in the way would probably only experience a small current passing through it, so sparing it from death. Only fish very near the water's surface would be killed. A fish as little as a foot below the surface would probably be quite safe."
2. HOW MUCH DOES THE SKY WEIGH?
Expert answer from the Science and Technology Facilities Council's Space Science and Technology Department: "If you want the total weight then it's about one millionth of the mass of the Earth, which is the equivalent of 570,000,000,000,000 adult Indian elephants."
3. WHY CAN'T PEOPLE LEAVE OTHER PEOPLE ALONE?
Philospher Mark Vernon suggests this approach. "Human beings are social animals, like ants; we thrive when we live well together, in families and communities. But unlike ants who just get on, humans make friends and enemies. It's then that we can't let others be.
"Or, a really short answer: As we make friends, so we make enemies."
4. WHY AREN'T BIRDS ELECTROCUTED ON WIRES?
Expert answer from the Space Science and Technology Dept: "Being electrocuted involves a current passing through you. For a bird to be electrocuted it would need to touch two wires at different voltages, or one wire and the grounded structure of the pylon, at the same time. If they did this there would be a current flow and the bird would be likely to be electrocuted. However this is very unlikely to happen and electricity authorities also give considerable thought to the design of their pylons to minimise the chance of birds being electrocuted."
5. WHAT IS TIME?
Expert answer from the Space Science and Technology Dept: "This is a difficult question to answer. Some scientists may call time the flow of cause and effect. A more detailed explanation could be, according to the Theory of General Relativity, that time is the path which an object will take through a four dimensional universe when left to itself. In such a universe, the four dimensions are indistinguishablefrom one another: they are not three dimensions of space and one of time. Such an approach can be used to explain the time dilation of special relativity - that time slows down as one approaches the speed of light in a vacuum - but this is not an argument that is accepted by all scientists."
6. WHY IS THE MOON SOMETIMES OUT IN THE DAY, TOO?
Expert answer from the Institute of Physics: "When the Moon revolves round the Earth, half of the time it is on the same side of the Earth as the Sun, and the rest of the time, they are on opposite sides. When the Moon and Sun are on the same side, the Moon is 'up' during the day. When they are on the opposite sides, the Moon is 'up' during the night. So surprise, surprise, the Moon is up during the day as often as it is up at night."
7. WHY DID GOD LET MY KITTEN DIE?
Mark Vernon's answer: "No-one knows for sure, though many people have tried to find an answer. What we do know is that when people and pets die, we care for them all the more, which says a lot about why compassion is so important."
Or, a really short answer: "No-one knows, but you know you care."
8. WHY DO I LIKE PINK?
Mark Vernon says:"Favourite colours unconsciously remind us of things that we find pleasurable or valuable. Pink is often associated with fun, like pink sweets; or the feminine, like pink clothes. Sweets are pleasant; the feminine is valuable."
His really short answer? "Pink reminds you of other things you like."
And psychologist Dr Stephen Briers, of the Science: So what? So everything campaign, says: "Traditionally it is thought girls like pink more than boys do. Scientists have found there may be a biological basis for why girls prefer pink, or at least more reddish colours than boys. Research has found that although more people prefer blue, women tend to prefer pinker shades. Some biologists say that this is because in Stone Age times a woman's role was to pick out reddish-coloured fruit, so they became more sensitive to reddish colours. Another scientist has suggested females may also prefer reddish colours because they need to be more able to spot when their children are ill with a fever (and therefore have a more reddish tone to their faces), or because changes in skin colour can let you know what a person is feeling and help females to read emotions better."
9. WHY IS WATER WET?
Expert answer from Stephanie Bell, of the National Science and Engineering Week: "There are two answers to this question: One answer is about what makes liquids stick to surfaces and 'wet' them - which is to do with forces between molecules. Water molecules are 'polar' - the arrangement of electrons means that electrical charge isn't evenly spread - and this makes water particularly attracted (electrically) to many surfaces. It also causes water to have lots of other interesting properties.
"But why does water feel wet? This is for a completely different reason. When you have water on your clothes or skin, it normally evaporates into the surrounding air. Evaporation produces cooling, because it takes energy. The feeling of wetness is actually coldness. You can test this by comparing water with another liquid - cooking oil - which doesn't evaporate so freely. Fill two small cups (egg-cups are ideal) - one with water, and the other with cooking oil. (Young children should ask an adult to help.) Let both liquids come to room temperature for a day, or overnight. Dip one index finger in each liquid, lift them out, and then observe for a few minutes."
10. WHY DOES MY BEST FRIEND HAVE TWO DADS?
Mark Vernon says: "People meet and fall in love. It's an old story. Ideally, their love grows, and they may raise children, as an expression of that love. Usually, a man and a woman fall in love and have kids. But it can be two women, or men."
And his really short answer: "Two men, and two women, can fall in love too."
