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A. Grey hair is caused by the loss of melanin, the pigment in our hair that gives it colour, over time. Melanin is produced by cells called melanocytes. Melanocytes eventually die and so stop
00:00 Mon 02nd Jul 2001A. Because perfume contains alcohol. Alcohol is a drying agent; it evaporates at a relatively low temperature, around 20 degrees Celsius. Keeping perfume away from light and warmth slows down the
00:00 Mon 02nd Jul 2001A. The dead keratin filled cells of the outer skin absorb water, however, the underlying live ones dont. The outer layer swells with the water, increasing its surface area. Because the skin on
00:00 Mon 25th Jun 2001A. Because the pressure in the aircraft is reduced gradually to a safe level, rather than achieved in one go. So your ears pop as they respond to this gradual change. Q. What is the highest
00:00 Mon 25th Jun 2001 A. Yes, it is, but it only acts as a rough guide and isn't as accurate as a real compass. Just point where the hour hand is at the sun then look where the 12 o'clock point is, the halfway point
00:00 Mon 25th Jun 2001A. A living person has almost the same density as water. If the person is alive and breathing, they will float, but if they drown they exhale and sink as water takes the place of air in the lungs.
00:00 Mon 18th Jun 2001A. You probably don't think about it when you wash your hands or clothes, but the cleaning process actually occurs at the molecular level. Soap works by interfering with the bonds that dirt and the
00:00 Mon 18th Jun 2001A. 'Geo' means earth, and 'thermal' means heat, so geothermal means 'earth heat'. Geothermal energy is produced by the heat of the earth and is normally found in volcanic and seismically active
00:00 Mon 18th Jun 2001A. The reason behind this unusual, sometimes embarrassing, often irritating condition isnt fully understood. Explanations proffered by the medical establishment range from an ancient remnant
00:00 Mon 11th Jun 2001A. Asked Isaacr recently. Here The AnswerBank has an in depth look at how speed cameras work. How do speed cameras work There are two main types of speed camera around at the moment, fixed speed
00:00 Mon 11th Jun 2001A. Motion sickness occurs when our sense of balance and equilibrium are disturbed. We naturally sense our spatial orientation: which way we are facing and moving, whether we are turning or standing
00:00 Mon 11th Jun 2001A. 'Red eye', the amateur photographers bugbear, is most common with cameras that have built-in or camera-mounted flash, where the flash unit is closest to the lens. This configuration means that
00:00 Mon 04th Jun 2001A. Carbon is stored in many forms on Earth, mainly in the oceans and fossil fuels. However, trees also store large amounts of the Earth's carbon. These natural carbon storage systems are known as
00:00 Mon 04th Jun 2001Thanks to DOUBRIS for this question. A. Yes they do and have done since 1886, when the Swiss Army decided to equip every soldier with a regulation single-blade folding knife. Q. But I thought
00:00 Mon 04th Jun 2001A. Your can of fizzy drink is carbonated, the carbon dioxide is under pressure in the can so that the gas dissolves in the drink. Once opened, the gas will eventually escape the depressurised can.
00:00 Mon 28th May 2001A. Humans have been harnessing wind power for over 2000 years, the first windmills were built in Persia. Wind farms are a very modern way of utilising wind: a pollution free renewable resource.
00:00 Mon 28th May 2001A. By using a chemical dating technique called radiocarbon dating. Q. When was radiocarbon dating discovered A. By a team of scientists led by the late Professor Willard F. Libby of the
00:00 Mon 28th May 2001 A. Thanks to djtaz11398 for this question recently to see Sensei's answer click here. Basically, it depends how good YOUR diet is! Stick to fresh food where possible when feeding your dog, also
00:00 Mon 28th May 2001A. This phenomenon, known as 'the orange juice effect' has been widely studied. The nasty flavour is caused by the detergent added to toothpaste. The detergent, the most commonly used one is
00:00 Mon 21st May 2001A. It's a new invention, inspired by the vertical climbing abilities of geckos, that allows humans to climb up walls. It is the brainchild of Gerald Winkler, from Herzogenaurach, Germany.
00:00 Mon 21st May 2001
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