|How Big, How Long, How Far, How Fast, How Many ...|
(Hint: click on the blue squares to find the answers to the purple questions)
Introduction For hundreds of years scientists have investigated the ways in which our world works and the many ways in which its workings can be described including biological, chemical, physical and so forth. For the most part the scientists observations and explanations (theories) have been descriptive but the new science - the science of the late twentieth century - has introduced a more quantitative (mathematical) aspect to science. The color red is no longer simply red but can be described in terms of its wavelength, frequency or velocity. This change in how science can explain things has come about through the development of technology which has produced tools that enable us to make such measurements.
1. How big is an acre? An acre was the descriptive name given in about 1300 AD to the amount of land that one man with his oxen and plough could plough in one day. This amount tended to vary since some land is easier to plough than others but now, in the U.S., one acre is 4,840 square yards; 640 acres is one square mile.
2. How big is a barleycorn? Well, it is actually one third of an inch long (3 barleycorns = 1 inch) but this 15th Century term is rarely used these days. When the term barleycorn (meaning an actual barley corn from the middle of an ear of barley) was common, it was also general practice to consider that the weight/mass of 1 barleycorn = 1 grain. The unit 1 grain is still in common usage but without any reference to barleycorns.
3. How small is a nanosecond? A nanosecond is a tiny unit of time that in the US is one billionth of a second and in the UK is one thousand-millionth of a second. (You need to remember that a billion in the US is 1,000,000,000 or one thousand-million but in the UK a billion is 1,000,000,000,000 or one million-million!)
4. How long is a musical note? Two crotchets equal one minim; two minims equal one semibreve; and two semibreves equal one breve. A breve is a double whole note.
5. How fast must a good pianist be able to play? To play some parts of an etude by Chopin a pianist needs to be able to read and play 3,950 notes in two and a half minutes. A piece (Mouvement Perpetuel) by Weber requires the pianist to play 4,541 notes in less than four minutes.
6. How fast can a bird fly? The spine-tailed swift has been timed at 106 miles per hour (mph). The highest average speed in level flight over a long distance is probably that of a carrier pigeon which has been timed over a distance of 186 miles at 97.40 mph. The peregrin falcon can reach speeds of 180 mph when diving for its prey; and some waterflowl can fly at up to 70 mph.
7. Which animal typically travels the slowest - tortoise, snail, caterpillar, earthworm or housefly? A tortoise travels at about 5 yards/minute; the snail at 23 inches to 55 yards/hour; the earthworm at 18 yards/hour; the housefly at 5 miles/hour. The microscopic amoeba travels at less than half an inch per hour.
8. How fast does wind blow? A cyclone moves along at 12 to 21 miles per hour (mph), but its winds are whirling around at several hundred miles an hour. The windiest place in the world is near the South Pole, the windiest place in the United States is Mount Washington in New Hampshire.
9. How fast does sound travel? Sound travels at different speeds through different media. Through dry air at sea level and at freezing point (0 degrees Centigrade/Celsius), sound travels at about 5 seconds per mile. Sound travels a bit faster as the temperature of the air rises above 0 degrees Celsius but never travels anywhere near as fast as light. Can you think what natural phenomenon demonstrates this very clearly? Think about thunder and lightning storms. Which do you notice first, the light of the lightning or the sound of the thunder?
10. How fast does light travel? Light travels through the vacuum of space at 299,793 km per second (which is 1,079,252,960 km per hour); or 186,282 miles per second (which is 670,619,880 miles per hour). The speed of light is not constant; it travels about 3 percent more slowly through air and much more slowly through glass or water.
11. How long is a day? A day is 86,400 seconds or 24 hours long which is the time it takes Earth to rotate once on its axis. This is measured by observing the movment of the Sun relative to a fixed point on Earth.
12. How long is a year? A year is the length of time that it takes Earth to make a complete revolution around the Sun. Technically this is exactly 365 days, 5 hours, 48 minutes and 45.51 seconds.
13. How long is it since the Age of the Dinosaurs on Earth? In late Permian times (at the end of the Paleozoic Era, about 230 million years ago) some scaly-skinned, egg laying repties evolved and gradually came to dominate animal life on Earth for many millions of years. These were the dinosaurs. It is probably about 65 million years since the last dinosaur lived on Earth. Many modern animals, including humans, had not yet evolved when the last of the dinosaurs died.
14. How many years will an animal live? The life expectancy of a cat is between 13 and 17 years. A mouse might live for 2 to 3 years; an owl for as many as 24 years; a dolphin for 65 years; and a tortoise for perhaps 100 years. Humans may live for 70 years or more but most of the cells in a human body do not live as long as a year and have to be continually replaced. Cells on the outer layers of the skin last for between 19 and 34 days. They are continually replaced by the growth of new cells in the germinal layer of the skin. The cells of the stomach lining last for only a couple of days.
15. How many karats in pure gold? Pure gold (chemical symbol Au) is a highly valued metal that is too soft and ductile to be suitable in its pure form for jewellry such as rings or as settings for precious gems. Consequently gold is typically alloyed with silver (Ag) or copper (Cu) to make it stronger and appropriate for its intended use.
16. How long does it take a common cold to develop? In medicine the time that it takes after infection by a bacterium or virus for the onset of an illness is called the incubation period. The incubation period for a common cold can be as short as 2 hours but can be up to 72 hours.
17. How strong is an earthquake? Charles Richter (1900-1985), an American seismologist, created a logarithmic scale that expresses the strength of earthquake shocks. An earthquake that is only detectable by sensitive seismographic machines is strength 2.0 to 2.9; slight vibration and swinging of hanging objects is indication of a strength 3.0 to 3.9 earthquake. In a level 7.0 to 7.9 earthquake buildings collapse, cracks appear in the ground and landslides occur. The scale is a logarithmic scale and a level 4.0 earthquake is ten times stronger than a level 3.0.
18. How many octaves? The word octave is used in several contexts including music, time and chemistry.
19. How many twos and threes? There are many words to express the quantity 2 (two) such as: pair, couple, brace, duo, duet, double, twosome, deuce, twofold, duplex, dual, twice, second, binary, etc.
20. How many blood cells? The cells in mammalian blood that transport oxygen atoms around the body are the red blood corpuscles (erythrocytes). They contain hemoglobin (haemoglobin) which is the compound onto which the oxygen is attached as the blood passes through the capillaries in the lungs.
21. How many ones and zeros? The number system that we are most familiar with is the base-ten decimal system. In this system the sequence of numbers is 1,2,3,4,5,6,7,8,9,10; then 11,12,13,14,15,16,17,18,19,20; etc.
22. How big is a billion? The answer to this question is not as clear cut as you might expect. Of course, everyone knows that one million is a number with six zeros and is one thousand thousand (1,000,000). But, not everyone knows (although most people do) that while the number one million is the same magnitude (size) around the world, the number one billion may not mean the same in the UK as it does in the US.
23. How heavy is a ton? The answer will depend upon which part of the world you are in. If you are in the US the ton weighs two thousand (2,000) pounds and is called a short ton. If you are in the UK your ton will weigh two thousand, two hundred and forty (2,240) pounds and will be called a long ton. As you can see it is very important in international dealings to make sure that you clarify just which weights and measures you are dealing with. (Fortunately, ounces and pounds weigh the same in both the US and the UK systems.)
24. How much milk in a pint? And, how much petrol (gasoline) in a gallon? This will depend upon where you are! Of course pints and gallons are slowly being replaced with a universal, standard - the metric system - but until this change is completed the differences in apparently same measurements can be a problem.
25. How far is a mile? The mile was originally a Roman unit measurement of distance and was 1,000 double-paces; one Roman mile is generally considered to have been what we would now describe as 1,618 yards.
26. How far is a sea mile? Well, while a statute mile (on land) is 1,760 yards, a nautical (at sea) mile is approximately 2,028 yards by UK standards, and approximately 2,025 yards by US standards.
27. How fast is a knot? (There is a wonderful opportunity here for making a pun - you do it though, not us.)
28. How far is it From Earth to the farthest edge of our Galaxy? It is approximately 75,000 light years.
29. What units are used in the International System of Units? Because the world has developed such a variety of illogical, imprecise and confusing measurements, french scientists have devised a universal standard - the System Internationale de Unites which uses the metric system as its base. Most countries in the world (except the US) have accepted the new system and most are using it - particularly in science.
30. How many atoms? In the Periodic Table of (Chemical) Elements originally devised in 1869 by the chemist Mendeleev and augmented over the years with newly discovered elements there are more than 100 elements. (And therefore there exist over 100 types of atoms.) Under normal conditions atoms do not exist separate from each other; they are always in groups joined together as molecules. The great variety groupings of atoms into molecules provides a wonderful range of chemical substances.
31. How often should I take my medicine? The prescription written by a doctor uses a short-hand that derives from Latin to let you know how to take the medicine being prescribed. Here are some of the terms the doctor uses:
Question: What is the meaning of Q.2h. ?
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