Icon Books

  • dvfgfmv9jmfez uma citaçãohá 5 meses
    body, your body, to explore the most extreme aspects of science. It’s all there. Everything from the chemistry of indigestion to the Big Bang and the most intractable mysteries of the universe is reflected in that single, compact structure. Your body will be your laboratory and your observatory.
    You can look at the whole body, treating it as a single remarkable object. A living creature. But you can also plunge into the detail, exploring the ways your body interacts with the world around it, or how it makes use of the energy in food to get you moving. Zoom in further and you will find somewhere between ten and 100 trillion cells. Each cell is a sophisticated package of life, yet taken alone a single cell is certainly not you. Go further still and you will find complex chemistry abounding – you have a copy of the largest known molecule in most of your body’s cells: the DNA in chromosome 1.
    Continue to look in even g
  • dvfgfmv9jmfez uma citaçãohá 5 meses
    traditional numbers become clumsy; a typical adult is made up of around 7,000,000,000,000,000,000,000,000,000 atoms. It’s much easier to say 7 × 1027, simply meaning 7 with 27 zeroes after it. That’s more than a billion atoms for every second the universe is thought to have existed.
    There’s a whole lot going on inside that apparently simple form that you see standing in front of you in the mirror.
    On reflection
    In a moment we’ll plunge in to explore the miniature universe that is you, but let’s briefly stay on the outside, looking at your image in the mirror. Here’s a chance to explore a mystery that puzzled people for centuries.
    Stand in front of a mirror. Raise your right hand. Which hand does your reflection raise?
    As you’d expect from experience, your reflection raises its left hand.
    Here’s the puzzle. The mirror swaps everything left and right – something we take for granted. Your left hand becomes your reflection’s right hand. If you close your right eye, your reflection closes its left. If your hair is parted on the left, your reflection’s hair is parted on the right. Yet the top of your head is reflected at the top of the mirror and your feet (if it’s a full-length mirror) are down at the bottom. Why does the mirror switch around left and right, but leave top and bottom the same?
  • dvfgfmv9jmfez uma citaçãohá 5 meses
    The book in the mirror is printed in mirror writing, swapped left to right.
    The reflected book is as far behind the mirror as my book is in front of it.
    The book’s colours are the same in the mirror as they are on my side.
    The front cover of the book in the mirror is the back cover of my book.
    Just take a look at that last statement. If I simply consider the book in the mirror to be an ordinary book then, as I look at it, my book’s back cover has become the mirror book’s front cover. Lurking here is the explanation of the mirror’s mystery. It doesn’t swap left and right at all. It swaps back and front.
    In effect, what the mirror does is turn an image inside out. The back of my book becomes the front of the book in the mirror. Put the book down and look at your own reflection again. Imagine that your skin is made of rubber and is detachable. Take off that imaginary skin, move it straight through the mirror and, without turning it round, turn it inside out. The point of your nose, which was pointing into the mirror is now pointing out of the mirror. The parts of you that are nearest the mirror are also nearest in the reflection. Your entire image has been turned inside out.
    In reality there is no swapping of left and right, so you don’t have to explain why the mirror handles this differently from top and bottom. The reason we have the illusion of a left-right switch is down to your brain. When you see your reflection in a mirror your brain tries to turn the reflection into you. It makes a fairly close match if it rotates you through 180 degrees and moves you back into the mirror.
  • dvfgfmv9jmfez uma citaçãohá 5 meses
    scope, use that, but otherwise use a magnifying glass.
    That strand of hair is going to start us off on everything from philosophy to physics. Dubious about just how philosophical hair can be? Consider this: you are alive and that hair is an integral part of you (or at least it was until you pulled it out). Yet the hairs on your body are dead – they are not made up of living cells. The same is true of fingernails and toenails. So you are alive, but part of what goes to make ‘you’ is dead.
    Remember that next time a TV advert is encouraging you to ‘nourish’ your hair. You can’t feed hair. You can’t make it healthy. It’s dead. Deceased. It has fallen off its metaphorical perch. Worried that your hair is lifeless? Well, don’t be. That’s how it is supposed to be. It’s quite amazing just how many hair products are advertised us
  • Xena Avancefez uma citaçãohá 2 anos
    It is not the strongest of the species that survives, nor the most intelligent, but the ones most responsive to change.
  • Ivana Popovićfez uma citaçãohá 3 meses
    We don’t respond to the world as it is, we act in accordance with our own mental map of the world.
  • Julia Mykhaylovafez uma citaçãohá 2 anos
    Firstly, make sure that you take regular ‘time out’ to look at the bigger picture, and to work out what you want from life. You get so caught up in the rat race of life that it usually takes a crisis to make you step back and re-visit what your priorities are.
  • Julia Mykhaylovafez uma citaçãohá 2 anos
    the effort we put in equals the reward that we expect to get as a result of our effort.
  • Julia Mykhaylovafez uma citaçãohá 2 anos
    if you want to achieve something really difficult, in order to be able to keep putting in sustained effort and to succeed, you have to really want to achieve your goal.
  • Julia Mykhaylovafez uma citaçãohá 2 anos
    The more you want to achieve the goal and the more you can enjoy the achieving of it, the better motivated you will be to put the effort into it.
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