CHRISTMAS CRACKED; EVERYTHING YULE NEED TO KNOW ABOUT DECEMBER 25 Why do we fall asleep after Xmas dinner? Why does Rudolf have a red nose? How do you crack a Brazil?
DOES champagne really keep it's fizz if you stick a spoon in the open bottle? How do you make the perfect snowball? Why do we fall asleep after a big Christmas dinner. Why do Brazil nuts always break when you crack them open? And WHY do we still have sprouts with our turkey? With just 23 days to go RACHAEL BLETCHLY got to grips with the science behind some Christmas conundrums...
WHY do crackers crack?
CRACKERS contain two strips of card, stuck together at their tips. These have combustible chemicals and fine sandpaper. on them. When the ends are pulled, the pieces of card rub together, and the friction from the sandpaper heats up the chemicals which go bang.
HOW do you crack a Brazil nut without squashing it?
THE crosssection of a Brazil nut is a triangle, with a slightly shorter base, to which the nut is attached. Most people try to crack it open ACROSS the base, squashing the nut and destroying it. But if you crack it across the sides, the shell will split neatly. The perfect Brazil nuts in chocolates are boiled first until the shell softens.
WHY does Rudolph have a red nose?
HE'S got a rotten cold. Reindeer noses contain a maze of membranes which heat the cold air they breathe in. But the moist conditions are perfect for parasites and bacteria - including 20 that are unique to Reindeer. Scientist Odd Halvorsen from the University of Oslo claims Rudolph's bright red nose is probably due to a parasitic infection of his respiratory system.
WHY does frost form only on the edges of holly leaves?
FOR water droplets to form frost, the damp air needs to come into contact with a cold object - in this case, the holly leaf. At the sharp tips and edges, the surface area is greater, exposing them to more of the damp air. The leaves are also waxy on their top surfaces, so any droplets that form there are more likely to run off and not turn into frost.
HOW does a teaspoon stuck into an open bottle of champagne make it stay fizzy overnight?
IT DOESN'T. This is an urban myth. People leave spoons in their bottles and find the wine is still fizzy the next day, so they presume the spoon was the reason. However, if you leave an opened bottle of champagne overnight with no spoon in the neck, it will be just as fizzy in the morning. The truth is that champagne simply takes a very long time to lose its fizz.
HOW do you make the perfect snowball?
SNOW needs to be just the right temperature - warm enough to melt slightly and be formed into a ball but cold enough for it to reset once the pressure is released and maintain the shape as it's thrown. In extremely cold conditions, not enough pressure can be induced by the thrower and the snow remains a powdery, crumbly mess. In warmer conditions, the slushy snow will melt as it is squeezed into shape.
WHY do we always fall asleep after Christmas dinner?
AFTER a meal, levels of glucose in our blood are high and that can switch off the brain cells that normally keep us awake and alert. Sleepiness is the body's primitive way of telling us to relax and save energy once we have found and eaten our food. When we are hungry, the brain's neurons are not inhibited and we are alert enough to go in search of food.
WHO get more presents - men or women?
NORWEGIAN biologists reckon men get the best deal - as women are programmed to give more. Apart from being expert shoppers, it seems we have a primitive instinct to give gifts and strengthen social ties.
WHO invented electric Christmas lights?
THOMAS Edison, inventor of the first light bulb, also created the first strand of electric lights at Christmas 1880 and strung them outside his lab in New Jersey, USA. In 1895 American Ralph Morris saw a string of lights on a phone switchboard and decided to use them on his tree.
WHY does beer froth when poured into a dry glass, but not when you top it up?
FIZZY drinks are saturated with gas, which comes out when the drink is shaken or if it hits scratches or specks of dust... like inside a dry glass. Once the inside of the glass is wet, any crystals will have dissolved and any dust particles will have been washed away.
ARE Brussels sprouts really good for us?
YES - sprouts are very healthy... and the worse they taste, the BETTER they are for you. Sprouts contain allyl isothiocyanate which gives them their distinctive smell and taste. When eaten, it helps stop pre-cancerous cells developing.
WHY do helium balloons go flat so fast?
HELIUM gas atoms measure one ten-billionth of ametre so helium escapes quickly even through metal films used for party balloons.
WHY do snowflakes always form sixsided shapes?
ICE forms hexagonal crystals because of the shape of the molecular lattice created when water freezes. Snowflakes are loose collections of lots of these tiny crystals.
WHY is it colder at the South Pole than the North Pole?
THERE is no land at the North Pole, but the South Pole is at 2,800m above sea level on a mountain range. Temperatures fall the higher you go, so average winter temperatures at the South Pole are minus 60c, and at the North Pole ONLY - 30c.
WHAT time is it at the North Pole?
ALWAYS midnight. The International Date Line runs through the North Pole, leaving it between one date and the next.