st English Maths 1 ESO. Bilingual section at Modesto Navarro UNIT 7. METRIC SYSTEM MEASUREMENT. 1. INTRODUCTION TO THE METRIC SYSTEM. Wow, I have just flown in from planet Micron. It was a long flight, but I wanted to spend some time with you! My name is Maggie in your language (but you couldn't pronounce my real name!) When I first arrived I couldn't understand how you measure things, but my teacher taught me all about measurement, and I am going to tell you everything he taught me. The first thing Tom told me was that you can measure things using two different systems: Metric and US Standard. Today is my day and your day to learn Metric. My teacher says that if I understand 10, 100, and 1000 then it will be very easy to learn the metric system. I wish I had ten fingers! 2. LENGTH. Measuring how long a thing is, how tall it is, or how far it is, are all examples of length measurements. The metre is the most important unit of length. We write it m. UNIT 7. METRIC SYSTEM MEASUREMENT 1 st English Maths 1 ESO. Bilingual section at Modesto Navarro Tom says I must know above all: - Millimetres. - Centimetres - Metres. - Kilometres. Millimetres: The smallest units of length are called millimetres. A millimetre is about the thickness of a plastic credit card. Or about the thickness of 10 sheets of paper on top of each other. This is a very small measurement! Centimetres: When you have something that is 10 millimetres, it is 1 centimetre. A fingernail is about one centimetre wide. Metres A metre is equal to 100 centimetres. 1 metre = 100 centimetres The length of this guitar is about 1 metre. Metres can be used to measure the length of a house, or the size of a playground. Kilometres When you need to get from one place to another, you need to measure that distance using kilometres. A kilometre is equal to 1,000 metres. The distances from one city to another or how far a plane travels are measured using kilometres. UNIT 7. METRIC SYSTEM MEASUREMENT 2 st English Maths 1 ESO. Bilingual section at Modesto Navarro Final thoughts about measuring length: (write it in English next to the Spanish words): These units are powers of 10. Pay attention: Examples: Example: what happens if you need to measure a longer distance, like from your house to school? – Let’s say you live approximately 10 miles from school • 10 miles = 16093 metres - 16093 is a big number, but you can could add a prefix onto the base unit to make it easier to manage: 16093 metres = 16.093 kilometres (or 16.1 if rounded to 1 decimal place) UNIT 7. METRIC SYSTEM MEASUREMENT 3 st English Maths 1 ESO. Bilingual section at Modesto Navarro Example: • Now let’s try our previous example from metres to kilometres: 16093 metres = 1609.3 decametres = 160.93 hectometres = 16.093 kilometres Those measurements are useful for things in everyday life... ... But how do we talk about really big and really small things? Please, continue reading. LARGE NUMBERS: We use Metric Number Prefixes like "kilo" (a thousand) and "milli" (one thousandth) and add them in front of the measurement. So something that is 1,000 metres is a "kilometre". Here is a quick summary of the special prefixes: Large Numbers Name deca hecto kilo mega giga tera peta Exa zetta yotta Symbol da h k M G T P E Z Y Factor 101 102 103 106 109 1012 1015 1018 1021 1024 Example: A million metres is called a megametre and abbreviated Mm. Also, to measure very large quantities we use “light years” and “astronomical units” (In Spanish UA). UNIT 7. METRIC SYSTEM MEASUREMENT 4 st English Maths 1 ESO. Bilingual section at Modesto Navarro SMALL NUMBERS: Here is a quick summary of the special prefixes: Small Numbers Name deci centi milli micro nano pico femto Atto zepto yocto Symbol d c m µ n p f A z y Factor 10-1 10-2 10-3 10-6 10-9 10-12 10-15 10-18 10-21 10-24 To measure small numbers we use “micro” and “millimicro”. Examples: Homework. Exercises 9, 10, 11, 12 and 13, page 127. UNIT 7. METRIC SYSTEM MEASUREMENT 5 st English Maths 1 ESO. Bilingual section at Modesto Navarro 3. WEIGHT Next, I wanted to eat some chocolate, so I had to learn about weight. Tom told me that to understand weights, I must know these three terms, above all: - Grams. - Kilograms - Metric tonne. Let’s take a few minutes and explore how heavy each of these are. - Grams: The gram is the most important unit of weight. Note: Do you know what a gram is? A gram is the mass of distilled water that there is in 1 cm3, weighed at sea level at a temperature of 4º C (= Un gramo es la masa de agua destilada que cabe en 1 cm3, pesada al nivel del mar y a una temperatura de 4º C). - Kilograms; 1000 grams = 1 kilograms. Kilograms are great for measuring things that can be lifted by people. Kilograms are often written as kg (that is a "k" for "kilo" and a "g" for “gram”), so "10 kg" means "10 kilograms". When you weigh yourself on a scale, you use kilograms. Tom weighs about 40 kg. How much do you weigh? UNIT 7. METRIC SYSTEM MEASUREMENT 6 st English Maths 1 ESO. Bilingual section at Modesto Navarro However, when things are very heavy, we need to use the tonne. - Tonne. 1000 kilograms = 1 metric tonne (Be careful: in the United Kingdom, a ton is around 1,016 kg, and in the USA a ton is around 907 kg). Tonnes (also called Metric Tonnes) are used to measure things that are very heavy. Things like cars, trucks and large cargo boxes are weighed using the tonne. This car weighs about 2 tonnes. Final thoughts about measuring weight: (Write it in English next to the Spanish words) Pay attention: Examples: UNIT 7. METRIC SYSTEM MEASUREMENT 7 st English Maths 1 ESO. Bilingual section at Modesto Navarro 4. CAPACITY. Since it was such a long flight, the first thing I could use is something cold to drink. But I want to know how much to ask for, so I can get a drink that is not too big or too small. Mainly, you need to know about millilitres and litres: Millilitres: A millilitre (that is "milli" and "litre" put together) is a very small amount of liquid. Here is a millilitre of milk in a teaspoon. It doesn't even fill the teaspoon! About 20 drops of water makes 1 millilitre! 1 teaspoon of liquid is about 5 millilitres: But a millilitre is definitely not enough for someone who is thirsty! So Tom told me about litres. - Litre: 1 litre = 1,000 millilitres So, the next time you are at the supermarket, take a minute and check out how many litres or millilitres are in each container! Do you know that…? A litre is the amount of distilled water there is in 1 dm3. UNIT 7. METRIC SYSTEM MEASUREMENT 8 st English Maths 1 ESO. Bilingual section at Modesto Navarro The final thoughts about capacity are: (write in English next to the Spanish words) And, pay attention: Examples: UNIT 7. METRIC SYSTEM MEASUREMENT 9 st English Maths 1 ESO. Bilingual section at Modesto Navarro EXERCISES UNIT 7. METRIC SYSTEM OF MEASUREMENT. LENGTH, WEIGHT AND CAPACITY. 1. Write in metres (Calculate in your mind): a) 2000mm b) 5 dm c) 4 hm d) 0.01km 2. Complete the gaps: a) 3 hm = __________ m b) 54 m = __________ km c) 5.07 km = __________ dm d) 46.75 dam = __________ cm 3. Complete the gaps: a) 3 cm = __________ dm b) 146 mm = __________ m c) 25.4 dm = __________ dam d) 16.5 m = __________ mm 4. Arrange from the smallest to the biggest: 4,378 m 4.3 hm 0.043 km 437,800 mm UNIT 7. METRIC SYSTEM MEASUREMENT 10 st English Maths 1 ESO. Bilingual section at Modesto Navarro 5. Complete: a) 5 hm = __________ m = __________ cm b) 5.4 m = __________ dam = __________ mm c) 47.03 km = __________ dam = __________ m d) 436.35 hm = __________ m = __________ cm 6. Spain has approximately 4,000 km of coastline. Write this length in metres and using scientific notation. 7. The dimensions of a football pitch are 119 m long and 91 m wide. Write these measurements in decametres and hectometres. 8. Use the calculator and complete: a) 4 U.A. = _________________________ km b) 3.5 años luz = _________________________ km c) 3.9 · 1013 km = _________________________ años luz d) 2.6 · 109 km = ________________________ U.A. 9. Complete: a) 0.05 mm = ____________________ b) 5.4 = ____________________ mm c) 17.8 m = ___________________ mm d) 0.0025 mm = ____________________ m UNIT 7. METRIC SYSTEM MEASUREMENT 11 st English Maths 1 ESO. Bilingual section at Modesto Navarro 10. Write in grams (calculate in your mind): a) 500 mg b) 30 dg c) 2 hg d) 0.8 dag 11. Complete: a) 4 hg = __________ g c) 96.7 kg = __________ hg b) 320 g = __________ kg d) 3.85 dag = __________ cg 12. Complete: a) 235 cg = __________ dag c) 145 cg = __________ hg b) 820 dag = __________ kg d) 503 g = __________ mg 13. Arrange from the smallest to the biggest: 378 dag 3.7 hg 0.037 kg 37,800 mg 14.