Measurement Mrs. Messina 6th grade Science
The Metric System The metric system is almost always used in scientific measurement. The Metric System is a DECIMAL based system. The Metric System is based on multiples of TEN. To measure length, we use a meter stick.
Measuring Length To measure length we use a meter stick or metric ruler. The units we use to measure length and their abbreviations are: 1.Meter (m) 2.Centimeter (cm) (1/100 of a meter) 3.Millimeter (mm) (1/1000 of a meter) 4.Kilometer (km) (1,000 meters)
Let s Look At The Ruler Look at the centimeter side of the ruler (METRIC side) 1)How many numbers do you see? 2) How many spaces are there between each written number? 3) How many longer lines are there between each written number?
Metric Ruler
Reading a Metric Ruler Never use fractions, like 2½. You must use decimals, like 2.5
Measuring Length How many millimeters are in 1 centimeter? 1 centimeter = 10 millimeters What is the length of the line in centimeters? Ruler: http://www.k12math.com/math-concepts/measurement/ruler-cm.jpg
DO NOW: How long is the purple line in cm? mm? How long is the green line in cm? mm?
Turn and Talk 1. Which is larger, a millimeter or a centimeter? 2. Which is larger, a meter or a kilometer?
Let s Complete The Activity Measure the items in centimeters as indicated below: 1)Paper clip 2)The clothes pin 3)The diameter of the penny 4)The top side of your interactive notebook 5)The calculator (long side)
Conversions When converting CENTIMETERS to MILLIMETERS, you need to multiply by 10. (You move the decimal 1 place to the right.) Example: 3.5 cm = mm 3.5 x 10 = 35 therefore, 3.5 cm = 35 mm
Convert Centimeters to Millimeters a) 10.5 cm = mm b)9.6 cm = mm c)3.8 cm = mm d)22.3 cm = mm e)0.7 cm = mm
Therefore, 54 mm = 5.4 cm Converting Millimeters to Centimeters When converting MILLIMETERS to CENTIMETERS, you will need to divide by 10. (Move the decimal one place to the left.) Remember if you do not see a decimal, it is at the end of the number. Example: 54 mm = cm 54 divided by 10 = 5.4
Practice: Converting Millimeters to Centimeters a)38 mm = cm b)79 mm = cm c)105 mm = cm d)15 mm = cm
Activity: Convert the items you measured in centimeters to millimeters. (Look back at your measurements.) 1) Paper clip 2) A clothes pin 3) The diameter of the penny 4) The top side of your interactive notebook 5) The calculator (long side)
DO NOW: Convert the following: a) 1.3 cm = mm b) 0.3 cm = mm c) 39 mm = cm d) 116 mm = cm
DO NOW: Convert the following: a) 3.4 cm = mm b) 23.1 cm = mm Millimeters to centimeters a) 14 mm = cm
Answer to the DO NOW: 3.4 cm = 34 mm 23.1 cm = 231 mm 14 mm = 1.4 cm
Mathematical Procedures to Adding Decimals: Remember Always line up your decimals when adding or subtracting. Example: 2.1 0.2 +.32 ans. 2.62
Practice with Adding Decimals a) 1.2 + 0.3 + 2.2 = b) 18.1 + 1.3 + 0.12 = c) 0.14 + 1.5 + 2.2 =
Answers: 1.2 + 0.3 + 2.2 = 3.7 18.1 + 1.3 + 0.12 = 20.6 0.14 + 1.5 + 2.2 = 3.84
AVERAGING When averaging, add up your numbers by first lining up your decimals. Then, divide by the amount of numbers you added up. Example: 18.3 + 3.3 + 30.36 = 51.96 Then divide 51.96 by 3 Answer: The average is 17.32
Practice: Find the average. a) 5 + 15 + 3 b) 3.3 + 0.9 + 30.3
Answers: 9 + 15 + 3 = 27 then, 27 divided by 3 = 9 (answer) 3.3 + 0.9 + 30.3 = 34.5 Then, 34.5 divided by 3 = 11.5 (answer)
DO NOW: 1) Take out yesterday s lab report. This will be handed in. 2) Complete the 3 questions on averaging on the first page of today s lab report. (Show all of your work.)
Question #1 If John s frog jumped 4 cm, then 3 cm, and then 2 cm, what is the average distance his frog jumped? 4 + 3 + 2 = 9 9 divided by 3 = 3 cm
Question #2 If Julia s frog jumped 3 cm, then 4 cm, and then 5 cm, what is the average distance her frog jumped? 3 + 4 + 5 = 12 12 divided by 3 = 4 cm
Question # 3 If Mark s frog jumped 2.5 cm, then 3.5 cm, and then 4.0 cm, what is the average distance his frog jumped? 2.5 + 3.5 10 divided by 3 = 3. 3 4.0 3. 3 cm 10. 0
DO NOW: What is an independent variable?
Answer to the DO NOW An independent variable is something that the scientist controls or changes on purpose.
Frog Jump HYPOTHESIS Example: If I jump a frog made out of green computer paper, then it will jump the farthest because the paper is lighter.
Procedure: 1) Get my materials. 2) Jump the green frog along the meter stick three times. 3) Record my measurements. 4) Jump my index card frog three times. 5) Record my measurements. 6) Find the average for each frog.
Mass
DO NOW: What is the difference between MASS and WEIGHT?
DO NOW: 1. What is the correct order in which you use the riders on the beam? 2. Before placing an object on the balance, you should make sure of what?
DO NOW: Label the parts of the triple beam balance. A B D C
MASS We use a TRIPLE BEAM BALANCE to measure the mass of an object.
Mass is the amount of matter in an object. Example: Matter in your body consists of blood, water, cells, organs, etc Mass is different from weight.
UNITS The unit used to measure the mass of an object is a grams. A gram is abbreviated as: g
WEIGHT Weight- is the force of gravity pulling an object toward the ground.
Up to 100 grams Up to 500 grams Up to 10 grams
Using the Triple Beam Balance 1. Make sure that all of the weights are moved to the left and are set on zero.
Using the Triple Beam Balance 2. Begin to align your pointer on the zero by slightly turning the adjustment knob under the pan.
Using the Triple Beam Balance 3) Once the pointer is leveled on zero, you will be ready to measure the mass of any object accurately.
Using the Scientific Method 1) PROBLEM: How many grams of sugar are in a piece of gum?
2) HYPOTHESIS IF we chew gum, THEN it will have less mass BECAUSE saliva will dissolve the sugar.
3) PROCEDURE/EXPERIMENT A) Measure the mass of the gum and the wrapper (unopened). B) Measure the mass of only the wrapper. C) Subtract the wrapper mass. Record data. D) Chew the gum until the sugar is gone. E) Place the chewed gum on the wrapper. F) Measure the mass of the chewed gum. G) Subtract the wrapper mass. Record data. H) Subtract the chewed gum mass from the new gum mass. Record data.
4) Collect DATA Mass of gum and wrapper Mass of only the wrapper Mass of gum BEFORE CHEWING AFTER CHEWING
5) CONCLUSION: Is my hypothesis correct or incorrect? *REFLECTION: Did you find out how much sugar is in a piece of gum? How did you do this?
Measure the mass of the wrapper around the gum
Measure the mass of the wrapper by itself
Measure the mass of the chewed up gum
Define MATTER Anything that has mass and takes up space. Mass is different from weight
RIDER Triple Beam Balance PAN BEAMS POINTER
Using your Mathematical Skills Add up your measured points by aligning the decimals. Example: 200 + 10 2.5 212.5
Turn and Talk With the people at your table, describe the steps for using a triple beam balance.
1) Wooden Block 2) Silver Block 3) Hand Lens 4) Clothes Pin 5) Paper Clip 6) Ruler 7) Bug 1 8) Bug 2 9) Bug 3 10) Bug 4 Mass Lab
DO NOW Review your study guide in preparation for the quiz today.
Volume and Volume of a Regularly Shaped Solid
DO NOW What is VOLUME?
Volume is the amount of space that an object occupies
Regularly shaped solids are measured with a metric ruler to determine: 1. Length 2. Height 3. Width
The formula for the volume of a regular solid is: Length x Height x Width = Volume (cm) (cm) (cm) (cm 3 )
What are the volumes of the boxes? 5cm A 5cm 5cm 4cm B 10cm 3cm 8mm C 3mm 2mm 2.5cm D 2.5cm 2.5cm
Do Now What is the formula for finding the volume of a regular shaped object (like a box)?
1. What is volume? The amount of space an object takes up 2. What is the formula used to find the volume of a regular shaped object? Length x Width x Height 3. What units do we use for volume of regular shaped objects? cm 3
DO NOW: What are the volumes of the regular shaped boxes below? 4cm 2cm 2cm 2cm 6cm 2cm cm3 cm3
Volume of a Liquid
To find the volume of a liquid we use an instrument called a graduated cylinder or a beaker.
Units for Volume of a Liquid We use units known as milliliters (ml) when measuring the volume of a liquid.
After pouring your liquid into a graduated cylinder, you will observe a natural curve that your liquid will form in the cylinder. The curved surface of the liquid is called a MENISCUS. *Meniscus the curved surface of a liquid
Do Now: Find the volume of the liquid. 40ml 35ml 30ml 25ml 20ml 15ml 10ml 5ml
DO NOW Define VOLUME
DO NOW What instrument do you use to find the volume of a REGULAR SOLID? What instrument do you use to find the volume of a liquid or an irregular solid?
Volume of an Irregularly Shaped Solid The volume of irregularly shaped objects is found by using the water displacement method.
Water Displacement Method 1. Pour water into a graduated cylinder 2. Record the start volume of the liquid 3. Add the irregular solid 4. Record the final volume 5. Subtract start volume from final to determine the volume of the irregular solid alone. (final start = volume of irregular solid)
Do Now: What are the volumes of the 2 objects below? Start Final Start Final 30 30 30 30 25 25 25 25 20 20 20 20 15 15 15 15 10 10 10 10 5 5 5 5
Do Now: What is the volume of the Start object below? Final 40ml 35ml 30ml 25ml 20ml 15ml 10ml 5ml 40ml 35ml 30ml 25ml 20ml 15ml 10ml 5ml
TEMPERATURE
Thermometer When you need to measure TEMPERATURE, we use a THERMOMETER.
THERMOMETER A thermometer is an instrument used to measure temperature. It consists of a thin, glass tube with a bulb on one end that contains a liquid (usually mercury or alcohol).
How does it work? A thermometer works because liquids expand when they are heated and contract when they are cooled.
Temperature Increasing When temperature increases, then the liquid in the bulb EXPANDS, causing the liquid in the bulb to rise up the column of the glass tube.
Temperature Decreasing When temperature decreases, then the liquid in the bulb CONTRACTS, causing the liquid to move down the glass tube.
Units of Measurement Temperature is measured in units called DEGREES.
Two Scales on the Thermometer The two scales on a thermometer are CELSIUS and FAHRENHEIT.
Most Common Scale The most common scale used to measure temperature is CELSIUS.
Weather Reporters Weather reporters use the scale known as FAHRENHEIT.
Freezing vs. Boiling CELSIUS: 0 degrees = the freezing point of water 100 degrees = the boiling point of water
Fahrenheit Fahrenheit 32 degrees = the freezing point of water 212 degrees = the boiling point of water