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The ABC’s of Science Intro to Life Science Measurement Metric System Part 1: Length Volume Science is all around us • Botany: the study of plants, uses PS to explain how plants use carbon dioxide (CO2) and water (H2O)to make food Science is all around us • Geology: explain earthquake waves and rock composition • Oceanography: chemistry of ocean water • Ecology: the nitrogen cycle and the transfer of energy between organisms in a food chain • Biology: how the heart pumps blood, how the eyes & ears work and how the brain sends electrical impulses throughout the body. What are the ABC’s of Science? A. The Metric System B. Safety Rules C. The Scientific Method --> We will be “reviewing” all of the above… pay attention, you will be tested on it! Mini-Contest • Which group can measure the length of the room the BEST? • In your group, plan (quietly and secretly) HOW you are going to measure the room. You have 3.5 minutes to plan • You may use any of the measuring tools on the counter. • Now, grab your tools and MEASURE (you have 4.5 minutes) Mini-Contest • Write down our answer on a sticky note. • Let’s see who got the answer. • Answer: the room is _________ long. • Did everyone get the same answer? • Why not? It all depends on the foot! • Numbers and units are used to make measurements. • The distance from your desk to my desk could be 25 shoe lengths or 30 shoe lengths. • It depends on how big the shoe is. • Think of Shaq’s foot versus Mini-Me. It all depends on the foot! • You can see that to use practical measurements, a measurement standard HAS to be used. • In other words, everyone has to use the SAME system or units. • Otherwise, it just gets confusing. Let’s talk Metric • A standard is a fixed quantity used by everyone when measuring. • Here in America we use an English system: foot, yard, and mile. • However, MOST people use another system called the International System of Units or SI (which stands for Système Internationale d’Unités) • This is the modern form of the metric system. Measurement • By using this system ALL scientists can understand each others measurements. • If I conducted an experiment here in America, even someone in Zimbabwe would be able to understand my measurements. • And, everything is done in multiples of 10, so changing from one unit to another is easier than with English units. Break it down • • • • • OK, let’s get this as simple as we can. We are going to look at all of our metric measurement units as two-part words. The first part is the PREFIX. The second part is the type of UNIT. So --> PREFIX - UNIT Part 1: the PREFIX •Here are some important prefixes: You need to memorize these Prefix Symbol Meaning kilocentimillimicro- k c m µ 1000 (1 thousand) 0.01 (1 one-hundredth) 0.001 (1 one-thousandth) 0.000001 (1 one-millionth) Part 2: the UNIT •Here are some important UNITs, and you need to memorize these too. What are we measuring? Length Volume Mass Temperature Unit meter liter gram kelvin Break it down yo’self! • One kilometer is equal to ____ meters. – kilo - meter • prefix = kilo or 1000 • meter = unit measuring distance • Therefore: 1 kilometer = 1000 meters. • 5 kilometers would be: – 5 x 1000 meters = 5,000 meters • Always remember to break it down! I still don’t get it. • Here’s another way to go from one unit to another; just remember: • King Henry Died of Drinking Chocolate Milk Mmmmmm. • King Henry Died of Drinking Chocolate Milk Mmmm i e e e e i i l c k c n l c o t a i t l r o i i o • To convert to a larger unit, move the decimal place to the left (divide) • To convert to a smaller unit, move the decimal place to the right (multiply) Let’s Practice 1. 10 grams = _____ kilograms • • Move the decimal three places to the left (divide) .01kg 2. 56 meters = _____ centimeters • • Move the decimal two places to the right (multiply) 5,600 cm 3. 876 centimeters = ____ kilometers • • Move the decimal five places to the left (divide) .00876 km Measuring Length Let’s talk Length • The meter (m) is the SI unit of length. • A meter is about the distance from a doorknob to the floor. • A driver golf club is also about a meter in length. • The meter is divided into 100 equal parts called centimeters (cm). • There are 100 centimeters in a meter: – 100cm = 1 m Measuring Length • An even smaller unit is a millimeter (mm). • The prefix milli- means 1/1000, so… – 1000 mm = 1 m – 10 mm = 1 cm • Long distances are measured in kilometers (km) • Note: here is the US, we measure speed by miles per hour, or mph. In most other countries, they measure in kilometers per hour. You try it! 4. Name 3 things that are about one meter long 5. Name 3 things that are measured in centimeters 6. Name 3 things that are small enough to be measured in millimeters Answers: 4. Meters: golf club, bath towels 5. Centimeters: your little fingernail, the distance between the lines on standard notebook paper, the width of a large paper clip 6. Millimeters: wire diameter, book thickness, tape width, camera film Let’s talk Volume • Have you ever heard someone say “this shampoo gives my hair a lot of volume!!!” • What does that mean? • Volume means to take up space. • Or, volume is the amount of space occupied by an object. • So if someone’s hair has a lot of volume, that means it is full. • It takes up a lot of space. Measuring Volume Measuring Volume of Solid Rectangular Objects • For solid rectangular objects, the volume is the length x width x height. • V = l x w x h • A cubic meter (m3) is a unit of volume. • A cubic meter is a very large unit - it contains 1,000,000 cubic centimeters. You try it! 7. What is the volume of this solid? • V=lxwxh • V = 4cm x 1cm x 2cm • V = 8 cm3 8. What is the volume of this solid? • V = 3cm x 3cm x 3cm • V = 27 cm3 Measuring Volume of Liquid Objects • For liquid objects, we use graduated cylinders to measure the volume. • In cooking, we may also use measuring cups, teaspoons or tablespoons. • The level of a liquid in a graduated cylinder shows the volume of the liquid. • A liter (L) is a unit that is usually used to express volume • A soft drink bottle is a 2-liter bottle. Measuring Volume • For smaller volume measurements, we also use: – milliliter (ml) – cubic centimeter (cm3). • One liter contains 1000 milliliters or 1000 cubic centimeters. • 1L = 1000ml = 1000 cm3 • 1mL = 1 cm3 Accuracy is Everything • To read the volume of the liquid, note the level at the bottom of the curve. • We call this the meniscus. You try it! 9. What is the volume in ml? – 73 ml 10. What is the volume in ml? – 21.5 ml Measuring Volume of Solid Irregular Objects • So, how would I measure the volume of an irregular object such as a piece of clay? • I can’t measure the sides and I can’t use a measuring cup. • But I CAN still use a graduated cylinder. • Simply submerge the object in the graduated cylinder and record the difference in water level. • We call this measuring volume by displacement. • You will practice it during the lab today. Measuring Volume of Solid Irregular Objects