agenda 24-sept: please find your seat! cw – pjas critique homework finish pjas critique write-...
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AGENDA 24-SEPT:AGENDA 24-SEPT:
Please find Please find your seat!your seat!
CW – PJAS CW – PJAS CritiqueCritique
HomeworkHomework Finish PJAS Finish PJAS
Critique write-Critique write-up and Essayup and Essay
PJAS #2 due PJAS #2 due tomorrow!tomorrow!
PJAS CritiquePJAS Critique Make a rough draft of Tasks #1-4 (5 if time)Make a rough draft of Tasks #1-4 (5 if time) FINAL COPY MUST BE WRITTEN IN INK FINAL COPY MUST BE WRITTEN IN INK
ON GRAPHING PAPER (per student)ON GRAPHING PAPER (per student)– Name/DateName/Date– TitleTitle– HypothesisHypothesis– Design DiagramDesign Diagram– MaterialsMaterials– ProcedureProcedure– Data (table and space for graph)Data (table and space for graph)– EssayEssay
Examples of testable, non-fact Examples of testable, non-fact hypotheseshypotheses
If a ball has a greater amount of If a ball has a greater amount of pressurepressure (lbs/in (lbs/in22), then it will ), then it will bounce higherbounce higher when dropped from when dropped from a fixed height.a fixed height.
Examples of testable, non-fact Examples of testable, non-fact hypotheseshypotheses
If you take If you take different colors of lightdifferent colors of light and shine them at an object then and shine them at an object then the objects will become different the objects will become different temperaturestemperatures..
Examples of testable, non-fact Examples of testable, non-fact hypotheseshypotheses
If the If the temperaturetemperature of Gatorade of Gatorade increases, then the conductivity increases, then the conductivity will will also increasealso increase..
AGENDA 25-SEPT:AGENDA 25-SEPT:
Turn/Review in Turn/Review in PJAS CritiquePJAS Critique
Notes – Notes – Scientific Scientific MeasurementMeasurement
HomeworkHomework
Think about Think about PJAS #3PJAS #3
Scientific MeasurementScientific Measurement
Mrs. FalatekMrs. Falatek
DefinitionDefinition
Comparison to a standardComparison to a standard
Metric SystemMetric System
Based on units of 10Based on units of 10 Used internationally and always in scienceUsed internationally and always in science
Base Units:Base Units:– Meter = lengthMeter = length– Liter = volumeLiter = volume– Gram = massGram = mass– Kelvin = temperatureKelvin = temperature– Ampere = currentAmpere = current
Measuring Distance...Measuring Distance...
LengthLength– Distance between two points. Distance between two points.
Measuring Volume...Measuring Volume...
VolumeVolume– amount of space occupied by an object. amount of space occupied by an object.
– The volume of a two dimensional, The volume of a two dimensional, rectangular object = rectangular object = length times its widthlength times its width. .
– The volume of a three dimensional The volume of a three dimensional rectangular object = rectangular object = length times width length times width times heighttimes height. . 1 mL = 1 cm1 mL = 1 cm33
Measuring Volume...Measuring Volume...
VolumeVolume– The volume of an irregularly shaped object The volume of an irregularly shaped object
is calculated by VOLUME DISPLACEMENT!is calculated by VOLUME DISPLACEMENT!
– See drawing on board.See drawing on board.
Measuring Temperature...Measuring Temperature...
TemperatureTemperature– is a measure of how much energy a is a measure of how much energy a
substance has. substance has.
– The SI unit for temperature is The SI unit for temperature is KelvinKelvin, K, K. . Other common units for temperature are Other common units for temperature are (ask class for examples) Celsius, C, and (ask class for examples) Celsius, C, and Fahrenheit, F. Fahrenheit, F.
PrefixesPrefixes
Each prefix represents a number (a Each prefix represents a number (a multiple of 10) that indicates the size of multiple of 10) that indicates the size of the measurementthe measurement
Mega Kilo Hecto Deca
Base Unit Deci Centi Milli Micro Nano Pico
(M) (k) (h) (da)
Gram (g)
Meter (m) (d) c (m) (n) (p)
Liter (L)
1000000 1000 100 10 1 1/10 1/100
1/1000
1/1000000
1/1x109 one
billionth
1/1x1012
one trilliont
h
PrefixesPrefixes
Example:Example:
Kilo means 1000Kilo means 1000 Milli means 1/1000 Milli means 1/1000
1.1. Convert 1 gram to kilograms: move decimal Convert 1 gram to kilograms: move decimal THREE places to the LEFT (0.001 kg)THREE places to the LEFT (0.001 kg)
2.2. Convert 1 gram to milligrams: move decimal Convert 1 gram to milligrams: move decimal THREE places to the RIGHT (1000 mg)THREE places to the RIGHT (1000 mg)
PrefixesPrefixes
cmcm
SizeSize WhatWhat
Metric EstimationsMetric Estimations
What metric unit would you use to describe What metric unit would you use to describe the following?the following?
1.1. The distance from the earth to the moonThe distance from the earth to the moon
2.2. The contents of a one gallon milk jugThe contents of a one gallon milk jug
3.3. Your weightYour weight
4.4. The length of an eyelash The length of an eyelash
5.5. The amount of soda in a canThe amount of soda in a can
AGENDA 26-SEPT:AGENDA 26-SEPT:
Factor Label Factor Label Method of Method of convertingconverting
CW – CW – conversions conversions mega sheetmega sheet
HomeworkHomework Conversions Conversions
Mega SheetMega Sheet PJAS #3 due PJAS #3 due
Friday!Friday!
The Factor Label MethodThe Factor Label Method
A method of converting between one quantity and A method of converting between one quantity and another.another.
Conversion factorConversion factor – describes the relationship – describes the relationship between two units (1 mm = 1000 between two units (1 mm = 1000 m)m)
4.5 m 1000 mm = _____ mm4.5 m 1000 mm = _____ mm
1m . 1m .
The Factor Label MethodThe Factor Label Method
Let’s complete #1-3 on your worksheet:Let’s complete #1-3 on your worksheet:#1)#1)
#2)#2)
#3)#3)
The Factor Label MethodThe Factor Label Method
Try this:Try this:The directions for an experiment ask each The directions for an experiment ask each
student to measure 1.84 g of copper wire. The student to measure 1.84 g of copper wire. The only copper wire available is a spool with a only copper wire available is a spool with a mass of 50.0 g. How many students can do the mass of 50.0 g. How many students can do the experiment before the copper runs out?experiment before the copper runs out?
The Factor Label MethodThe Factor Label Method
Try this:Try this:An experiment requires that each student use An experiment requires that each student use
an 8.5 cm length of magnesium ribbon. How an 8.5 cm length of magnesium ribbon. How many students can do the experiment if there is many students can do the experiment if there is 570 cm of magnesium ribbon available?570 cm of magnesium ribbon available?
The Factor Label MethodThe Factor Label Method
Let’s complete the calorie problem on the Let’s complete the calorie problem on the back of your worksheet:back of your worksheet:How many calories are there is 4 tsp of sugar?How many calories are there is 4 tsp of sugar?
The Factor Label MethodThe Factor Label Method
Try these:Try these:
Convert 8 hr to seconds.Convert 8 hr to seconds.
How many minutes are there in one week?How many minutes are there in one week?
AGENDA 29-SEPT:AGENDA 29-SEPT:
Submit work from Submit work from conversions mega conversions mega sheetsheet
CW – finish HW CW – finish HW side of side of conversions mega conversions mega sheetsheet
Measurement Pre-Measurement Pre-lablab
HomeworkHomework Part 1 – Part 1 –
Measurement Measurement LabLab
PJAS #3 due PJAS #3 due Friday!Friday!
AGENDA 1/2-OCT:AGENDA 1/2-OCT:
Check Part 1Check Part 1 Measurement Measurement
Pre-LabPre-Lab Measurement Measurement
LabLab
HomeworkHomework Part 2 – Part 2 –
Measurement Measurement LabLab
TEST NEXT TEST NEXT WEDNESDAYWEDNESDAY
Measurement Lab.Measurement Lab.
Modify procedure: Activity 2, Part III – use a Modify procedure: Activity 2, Part III – use a 50 mL graduated cylinder instead of a 100 50 mL graduated cylinder instead of a 100 mL.mL.
Materials are located against the walls Materials are located against the walls around the room. DESIGNATE ONE around the room. DESIGNATE ONE PERSON TO COLLECT MATERIALS PER PERSON TO COLLECT MATERIALS PER GROUP/PER ACTIVITY.GROUP/PER ACTIVITY.
Measurement Lab Write-upMeasurement Lab Write-upProcedure: …Procedure: …
Data & Conclusion:Data & Conclusion: Activity 1Activity 1
Data table 1&2Data table 1&2
Activity 2Activity 2Part I, II & Data table, IIIPart I, II & Data table, III
Activity 3Activity 3Part 1 & Part 1 & PLPL question, II Data table & question, II Data table & PLPL questions, IV questions, IV
Activity 4Activity 4 Data table and Data table and PL PL questionsquestions
Pre-Class:Pre-Class:
1 meter is equivalent to 3.2808 ft. 1 meter is equivalent to 3.2808 ft. Convert 1.25 meters to feet using the Convert 1.25 meters to feet using the correct conversion factor!correct conversion factor!
How would measure the volume of an How would measure the volume of an irregularly shaped object?irregularly shaped object?
You data is a measure of change in You data is a measure of change in temperature over time. Which type of temperature over time. Which type of graph would you use to represent your graph would you use to represent your data?data?
AGENDA 3-OCT:AGENDA 3-OCT:
Pre-ClassPre-Class Submit Submit
Measurement LabMeasurement Lab Notes – Density Notes – Density
and Sig Figsand Sig Figs CW – Density & CW – Density &
Sig Figs PracticeSig Figs Practice
HomeworkHomework Test Test
WednesdayWednesday Measurement Measurement
Review WSReview WS
Density is an INTENSIVE property.Density is an INTENSIVE property.
Density depends only on the composition of Density depends only on the composition of a substance, not on the size of the sample.a substance, not on the size of the sample.
Is defined as Is defined as mass per unit volumemass per unit volume..
Is calculated by Is calculated by dividing mass by volumedividing mass by volume. . Units are g/ml or g/cmUnits are g/ml or g/cm33..
Calculating DensityCalculating Density
Let’s try these:Let’s try these:A copper penny has a mass of 3.1 g and a A copper penny has a mass of 3.1 g and a
volume of 0.35 cmvolume of 0.35 cm33. What is the density of . What is the density of copper?copper?
A bar of silver has a mass of 68.0 g and a A bar of silver has a mass of 68.0 g and a volume of 6.48 cmvolume of 6.48 cm33. What is the density of . What is the density of silver?silver?
How do we measure density? How do we measure density?
Measure the area of a Measure the area of a REGULARLY REGULARLY SHAPED object to get SHAPED object to get its densityits density
Water displacement for Water displacement for IRREGULARLY IRREGULARLY SHAPED objects (like SHAPED objects (like a rock)a rock)
AGENDA 6-OCT:AGENDA 6-OCT:
Submit Submit Measurement Measurement Review WSReview WS
Notes – Sig FigsNotes – Sig Figs CW – Sig Figs CW – Sig Figs
PracticePractice
HomeworkHomework Test Monday Test Monday
10/1310/13
Significant FiguresSignificant Figures
Refers to the digits of a number of which we Refers to the digits of a number of which we are CERTAIN (no one would argue with us) are CERTAIN (no one would argue with us) plusplus
ONLY ONE of which we are UNCERTAIN (we ONLY ONE of which we are UNCERTAIN (we each might have a different digit as the final each might have a different digit as the final digit)digit)
Rules for Sig FigsRules for Sig Figs
SIGNIFICANTSIGNIFICANT1.1. All non-zero numbers (1 through 9)All non-zero numbers (1 through 9)2.2. All “trapped” zerosAll “trapped” zeros3.3. ENDEND and and AFTERAFTER = at the end of a number = at the end of a number
AND after the decimalAND after the decimal
NOT SIGNIFICANTNOT SIGNIFICANT1.1. Place holder zeros Place holder zeros
Counting sig figsCounting sig figs
IT’S THE ZEROS THAT ARE TRICKY!!IT’S THE ZEROS THAT ARE TRICKY!! How many sig figs here:How many sig figs here:
1.1. 109109 6.10906.1090
2.2. 20032003 7. 200307. 20030
3.3. 200200 8. 200.8. 200.
4.4. 0.365050.36505 9. 0.00365059. 0.0036505
5.5. 0.0020.002 10. 0.0020010. 0.00200
Significant FiguresSignificant Figures
MultiplyingMultiplying & & dividing dividing-- answers must contain the answers must contain the same number of significant figures as in the same number of significant figures as in the number that has the number that has the least amount of significant least amount of significant figuresfigures
AddingAdding & & subtracting subtracting - answers must contain the - answers must contain the same number of digits as in the number with the same number of digits as in the number with the greatest uncertainty greatest uncertainty (least number of decimal (least number of decimal places)places)
AGENDA 7-OCT:AGENDA 7-OCT:
Submit HomeworkSubmit Homework Notes – Scientific Notes – Scientific
NotationNotation CW – Scientific CW – Scientific
Notation Practice & Notation Practice & Accuracy/Precision Accuracy/Precision WSWS
HomeworkHomework Scientific Scientific
Notation WSNotation WS Test MONDAY Test MONDAY
10/1310/13
Scientific NotationScientific Notation
Shorthand number writingShorthand number writing
0.000000459 g = 0.000000459 g = 4.594.59 x 10 x 10--77 g g
4.594.59 x 10 x 10--77 g g1. 4.59 1. 4.59 = = mustmust be between 1 and 10 be between 1 and 10
2. 10 2. 10 = always base 10= always base 10
3.3. - - = tells= tells if original number is less than one (-) or if original number is less than one (-) or greater than one (+) AND greater than one (+) AND directiondirection you moved you moved decimaldecimal
4. 7 4. 7 = how many places decimal moved= how many places decimal moved
Try theseTry these
0.000870.000878.7 x 108.7 x 10-4-4
23,000,00023,000,0002.3 x 102.3 x 1077
269.23269.232.6923 x 102.6923 x 1022
0.003160.003163.16 x 103.16 x 10-3-3
Confusing Words in ScienceConfusing Words in Science
Accurate – a measure of how close a Accurate – a measure of how close a measurement comes to the actual measurement comes to the actual value of whatever is measure.value of whatever is measure.
Precise – a measure of how close a Precise – a measure of how close a series of measurements are to one series of measurements are to one another.another.
Confusing Words in ScienceConfusing Words in Science
In my own words…In my own words… Accurate = you’re Accurate = you’re
right!right!
Precise = a Precise = a bunch of numbers bunch of numbers are close togetherare close together
Accuracy and PrecisionAccuracy and Precision
Accurate = Accurate = you’re right!you’re right!
Precise = a Precise = a bunch of bunch of numbers are numbers are close togetherclose together
Accuracy and PrecisionAccuracy and Precision
To evaluate accuracy, you must To evaluate accuracy, you must compare your value to the correct compare your value to the correct value!value!
Error = experimental value – accepted Error = experimental value – accepted valuevalue
% Error = (error % Error = (error ÷ ÷ accepted value) x accepted value) x 100100
Calculating ErrorCalculating Error
During an experiment, I found the During an experiment, I found the boiling point of pure water to be 98boiling point of pure water to be 98°C, °C, however we all know the accepted however we all know the accepted value to be 100°C. Calculate the value to be 100°C. Calculate the percent error in my measurement.percent error in my measurement.
Error = 98Error = 98°C°C – – 100°C100°C
% Error = (2% Error = (2°C°C ÷ ÷ 100°C100°C) x 100 = 2%) x 100 = 2%