Measurement. Measurements science is based on measurements all measurements have: – magnitude – uncertainty – units Numbers mathematics is based on numbers.

Slides:



Advertisements
Similar presentations
CHEMISTRY 11 TODAY’s OBJECTIVE:
Advertisements

Physics Tool Kit Units (S.I. System - Meters, Kg, S) Unit Conversion Scientific Notation Accuracy and Precision Significant Figures Dimensional Analysis.
Chapter 2. Measurement Chemistry is a physical science, one that depends heavily on measurement to obtain quantitative data. Measurement is the determination.
Measurement vs. Number Significant Digits and Accuracy Exact numbers – number determined by counting or definition Approximate numbers – number determined.
Uncertainty and Significant Figures Cartoon courtesy of Lab-initio.com.
Chapter 2 Section 3.
Significant figures or Significant digits
Ch. 3.1 – Measurements and Their Uncertainty
Uncertainty in Measurements
Significant Figures (digits)
Significant Figures There are two kinds of numbers in the world: Exact
SIGNIFICANT figures Two types of numbers: exact and inexact. Exact numbers are obtained by counting or by definitions – a dozen of wine, hundred cents.
Ms. Pollock Significant Figures  Numbers in math class considered to be exact – produced by definition, not by measurement  Measurements.
Scientific Notation & Significant Figures in Measurement Dr. Sonali Saha Chemistry Honors Fall 2014.
IB Chem I Uncertainty in Measurement Significant Figures.
Objective: Differentiate between accuracy and precision.
1. To show how very large or very small numbers can be expressed in scientific notation 2. To learn the English, metric, and SI systems of measurement.
MeasurementsandCalculations. Numbers Numbers in science are different than in math. Numbers in science always refer to something grams 12 eggs.
Significant Figures.
Chapter 1.5 Uncertainty in Measurement. Exact Numbers Values that are known exactly Numbers obtained from counting The number 1 in conversions Exactly.
Uncertainty in Measurements: Using Significant Figures & Scientific Notation Unit 1 Scientific Processes Steinbrink.
Chem 160- Ch # 2l. Numbers from measurements.. Measurements Experiments are performed. Numerical values or data are obtained from these measurements.
“Uncertainty in Measurement”
Cup of coffee = ~ 200 ml Add drop of H 2 O = 0.05 mL New volume: ~200 mL or mL?? If you say you imply that the volume of the initial cup.
Measurement and Its Uncertainties.
Precision, Error and Accuracy Physics 12 Adv. Measurement  When taking measurements, it is important to note that no measurement can be taken exactly.
Measurements and Calculations 1. To show how very large or very small numbers can be expressed in scientific notation 2. To learn the English, metric,
MEASUREMENTS. EXACT NUMBERS! Numbers determined by counting or by definition Ex: 6 apples, 1 teacher 1 inch=2.54 cm.
Significant Figures Chemistry. Exact vs approximate There are 2 kinds of numbers: 1.Exact: the amount of money in your account. Known with certainty.
Unit 1 Chapter 2. Common SI Units SI System is set-up so it is easy to move from one unit to another.
Significant Figures and Scientific Notation The measuring device determines the number of significant figures a measurement has. Significant figures reflect.
MEASUREMENTS. What is the difference between these two measurement rulers? Should we record the same number for each scale reading? The second scale gives.
Significant figures (sig figs) How many numbers mean anything. When we measure something, we can (and do) always estimate between the smallest marks. How.
Significant Figures Significant figures in a measurement consist of all the digits known with certainty plus one final digit, which is somewhat uncertain.
Lesson 1-3a Accuracy, Precision and Certainty Pg 17 and 18.
Scientific Measurement Measurements and their Uncertainty Dr. Yager Chapter 3.1.
Slide 1 of 48 Measurements and Their Uncertainty
Accuracy and Precision Accuracy and Precision A MEASURE of your SUCCESS!
A. 3 Parts to any measurement 1. Numerical Value 2. Unit (denotes scale) 3. Estimate of uncertainty B. Lab Measurement-proper number of sig figs 1. Sig.
© Copyright Pearson Prentice Hall Slide 1 of Measurements and Their Uncertainty On January 4, 2004, the Mars Exploration Rover Spirit landed on.
The significant figures in a measurement Consist of all the digits known with certainty plus one final digit, which is uncertain or is estimated. What.
Slide 1 of 48 Measurements and Their Uncertainty
Introduction to Physics Science 10. Measurement and Precision Measurements are always approximate Measurements are always approximate There is always.
Scientific Notation & Significant Figures in Measurement.
1 INTRODUCTION IV. Significant Figures. A. Purpose of Sig Figs Units of Measurement: Measurements indicate the magnitude of something Must include: –A.
Significant Figures & Scientific Notation. Significant Figures Scientist use significant figures to determine how precise a measurement is Significant.
T ODAY I WILL : E XPLAIN S IGNIFICANCE IN M EASUREMENT T AKE PROPER MEASUREMENTS.
Scientific Notation A short-hand way of writing large numbers without writing all of the zeros.
The Science of Physics Chapter #1 Ms. Hanan Anabusi.
All measurements are subject to uncertainties. All instruments used are influenced by external circumstances, and the accuracy of a measurement may be.
Lesson 7-9 Precision and Significant Digits. Definitions Precision- a measure of exactness to which a measurement is made. Precision depends on the smallest.
SIGNIFICANT figures Two types of numbers: exact and inexact. Exact numbers are obtained by counting or by definitions – a dozen of wine, hundred cents.
CHEMISTRY CHAPTER 2, SECTION 3. USING SCIENTIFIC MEASUREMENTS Accuracy and Precision Accuracy refers to the closeness of measurements to the correct or.
Section 1–2: Measurements in Experiments Physics Pages 10–20.
Precision, Error and Accuracy Physics 12. Measurement  When taking measurements, it is important to note that no measurement can be taken exactly  Therefore,
Uncertainty in Measurement A digit that must be estimated is called uncertain. A measurement always has some degree of uncertainty.
What do you know about these words listed above?.
First-Year Engineering Program Significant Figures This module for out-of-class study only. This is not intended for classroom discussion.
Uncertainty in Measurement How would you measure 9 ml most precisely? What is the volume being measured here? What is the uncertainty measurement? For.
Significant Figures (a.k.a. Sig Figs). Significant Figures In science, measured values are reported in terms of significant figures. Significant figures.
 Importance: to ensure the accuracy of our measurements  To make sure we tell others only what we actually know based on our equipment and it’s limitations.
The Metric System Uncertainty in Measurements. System of Measurement English System – Traditionally used in the United States – Base units are interconverted.
This estimated number, 22.9°C, has three digits. The first two digits (2 and 2) are known with certainty, while the rightmost digit (9) has been estimated.
Calculating and using significant figures What’s the point why do scientist need to know them?
Numbers in Science Chemists deal with very large numbers
How big is the beetle? Measure between the head and the tail!
How big is the beetle? Measure between the head and the tail!
Significant Figures.
SIGNIFICANT FIGURES.
Significant Figures (Sig figs)
Presentation transcript:

Measurement

Measurements science is based on measurements all measurements have: – magnitude – uncertainty – units Numbers mathematics is based on numbers exact numbers are obtained by : – counting – definition

Measurements Measurements are not numbers – Numbers are obtained by counting or by definition; measurements are obtained by comparing an object with a standard “unit” – When you say that a table is 2 meters long, you are really saying that the table is two times longer than an object that is 1 meter long

Measurements Numbers are exact; measurements are inexact Mathematics is based on numbers; science is based on measurement

Uncertainty in Measurement Comparison with a unit or a scale of units always involves some uncertainty Estimate between the smallest scale divisions The digit between the lines is always uncertain (estimated)

Uncertainty in Measuring Devices There is a limit to the precision of a measurement The scientist making the measurement must decide the uncertainty value for a particular measuring device. See “Scale Reading, Uncertainty and Significant Figures”

Significant figures Significant figures are the digits in a measurement known with certainty plus one digit that is uncertain (estimated)