Scientific Notation The basics and some math. Take out your calculator. Write these calculations and the answer in your notes: 12,922,341 / 0.011 435 7 = 1,130,000,000 0.05 / 20,111 = 0.000 002 486 Re-writing numbers in SCIENTIFIC NOTATION makes it so we don’t have to deal with all of these “extra” zeros. What is it? Scientific Notation (Exponential Notation) Scientific Notation is used to express any number as: a number between 1 and 10 (called multiplied by 10 (the a coefficient) “base” as in “base 10”) raised to a power (indicated by an exponent) coefficient = 9.13 8 9.13x10 9.13E8 exponent = 8 First, let’s review exponents 10 = 10 (x 1) = 101 100 = 10 x 10 = 102 1,000 = 10 x 10 x 10 = 103 10,000 = 10 x 10 x 10 x 10 = 104 The Count the “0”s 1 2 3 4 number in the exponent tells you how many times ten is multiplied by itself. Reviewing Exponents Any number raised to the 0 power – or has a 0 in the exponent = 1. So, 100 = 1 Scientific Notation Base 10 cont. What does this really mean? 109 would equal a 1 followed by how many zeros? 9 1,000,000,000 What would 1.13 x 109 be if written in “long form?” Move the decimal place to the right 9 places. 1,130,000,000 When you have a positive exponent, move your decimal to the right the same number of places that are in the exponent. Let’s rewrite the first number we calculated in scientific notation. 12,922,341 / 0.011 435 7 = 1,130,000,000 1.13 x 109 What does this really mean? Scientific Notation Base 10 – negative exponents If the exponent is negative, think division. 10-1 = 1/(10) = 0.1 10-2 = 1/(10 x 10) =1/(100) = 0.01 10-3 = 1/(10 x 10 x 10) = 1/(1,000) = 0.001 10-4 = 1/(10 x 10 x 10 x 10)= 1/(10,000) = 0.0001 Move the decimal point to the left if you have a negative exponent. Let’s rewrite our second number in scientific notation. 0.05 / 20,111 = 0.000 002 486 Coefficient = 2.486 The decimal would have to be moved to the left 6 places, so our exponent will be 6. 2.486 x 10-6 Now give it a try with a partner. You have 5 minutes.