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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 (CO 2 ) and water (H 2 O)to make food. Science is all around us.
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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? • The Metric System • Safety Rules • 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. Wow, why didn't I think of that!
Let’s talk Metric • A standardis 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
Part 2: the UNIT • Here are some important UNITs, and you need to memorize these too.
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 • 10 grams = _____ kilograms • Move the decimal three places to the left (divide) • .01kg • 56 meters = _____ centimeters • Move the decimal two places to the right (multiply) • 5,600 cm • 876 centimeters = ____ kilometers • Move the decimal five places to the left (divide) • .00876 km
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! • Name 3 things that are about one meter long • Name 3 things that are measured in centimeters • 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 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 = l x w x h • 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.