Unit 1A:SCIENTIFIC MEASUREMENT INSTRUCTIONS FOR NOTETAKING: Copy ALL words & examples unless otherwise indicated. Copy NO tables or diagrams unless otherwise indicated. Use Cornell (2-column style) format. Leave room after each EQ for a 3 sentence summary.

Unit 1A:SCIENTIFIC MEASUREMENT OBJECTIVES (Don’t Copy!) Convert Between Standard Notation to Scientific Notation Identify Significant Figures & Uncertainty in Measurements Perform Operations with Significant Figures Addition & Subtraction Multiplication & Division

Scientific notation consists of two parts: 1. A number between 1 and 10 (the “coefficient”) 2. A power of 10 Ex: x 108 7.01

What is Scientific Notation? a way of expressing really big numbers or really small numbers. For some numbers, scientific notation is more concise.

Converting from StandardScientific Notation EX: Convert 289,800,000 to scientific notation. _______ x 10___ 2.898 8 STEP 1: Moving the decimal, convert this number so that it falls between 1 and 10. STEP 2: Count the number of places you moved the decimal. This is the exponent. If the number was large to start with, exponent is positive If the number was small to start with, exponent is negative

Examples Given: 0.000567 5.67 x 10 ___ -4 STEP 1 STEP 2 NOTE: This is a very small number, so the exponent is SMALL (negative) 5.67 x 10 ___ -4 ___________ STEP 1 STEP 2

Converting Scientific Notation to Standard Example: 9.301 x 10 -7 STEP1 : Using the sign on the exponent, decide which way to move your decimal. Negative sign, move to the left (negative direction) Positive sign, move to the right (positive direction) STEP 2: Move the decimal the same number of spaces as the exponent indicates. Use zeros to hold “empty” spaces.

Scientific Notation & Your Calculator Video Instructions- Using Calculator

Plugging Scientific Notation into My Calculator Find the button on your calculator that is used to enter SCIENTIFIC NOTATION. Write it HERE___ OR (Do Not Copy) Note: If you find one of the symbols ABOVE a key, rather than ON a key, you must push EE EXP 2nd EE 2nd EXP

Plugging Scientific Notation Into My Calculator Ex: Plug this number into your calculator: 8.93 x 1o-13 (leave the blanks empty for now) Write the steps you used below Type 8.93 Push ______ button. Type_____13_____ Push ____OR____ button What I see on the screen is _________ NOTE: Use your calculator’s keys if they differ from what is written here EE NOTE: Sometimes these 2 steps can be reversed +/- (-) 8.93 -13

Scientific Notation: Doing Calculations (copy the problem & table) Ex: 3 x 104 + 2.5 x 105 USE CALCULATOR: Problem 3 x 104 + 2.5 x 105 What you type 3 EE 4 2.5 EE 5 What you see on calculator 304 2.505 NOTE: Use your calculator’s keys if they differ from what is written in table & fill them in NOTE: Answers must be in scientific notation! Calculator says: 280000 Correct Answer: 2.8 x 105

Practice Calculator says: 0.0521 9.1 x 10-3 + 4.3 x 10-2 ANSWER: 5.21 x 10-2

Scientific Notation:Multiplying&Dividing (copy the problem & table) Ex: (6.1 x 10-3) (7.2 x 109) USE CALCULATOR: Problem 6.1 x 10-3 x 7.2 x 109 What you type 6.1 EE 3- 7.2 EE 9 What you see on calculator 6.1-03 7.209 NOTE: Use your calculator’s keys if they differ from what is written in table NOTE: Answers must be in scientific notation! Calculator says: 43920000 Correct Answer: 4.392 x 107

Uncertainty in Measurement There is a degree of uncertainty in every measurement. Here are some concepts to help us understand how reliable our measurements are! Accuracy precision error significant figures

Accuracy v. Precision (copy the table) What it is How do I measure it? Example Accuracy how close a measurement comes to the ACTUAL value of what is being measured Compare MEASUREMENT to ACTUAL VALUE to determine Precision how close a series of measurements are to one another. Compare 2 or more MEASUREMENTS to one another.

Accuracy v. Precision

Accuracy v. Precision copy question & leave room for your team answer Question for discussion: What causes a situation where there is HIGH precision but LOW accuracy?

Error in Measurement Error = experimental value – accepted value Ex: water boils at 100.0 °C Ex: thermometer reads 99.1°C Error = experimental value – accepted value (copy equation on P. Table) Error can be a + or – value Discussion Question: Is the example above POSITIVE or NEGATIVE error? Answer: Error = 99.1 - 100.0 °C Error = ____ ° C ( error is ____)

Error in Measurement: % Error Percent Error = | error | x 100 accepted value (copy equation on P. Table) Example | 100.0 - 99.1 °C | x 100 100.0 °C Answer: 0.9 % error