Physics
Vandebilt Catholic High School
Walt Dupre
Scientific Notation
Scientific notation is a shorthand way of expressing numbers that replaces decimal places with powers of ten.
N X 10e (Where "N" is the coefficient and "e" is the exponent.)
How to express numbers in scientific notation
- Move the decimal until only one digit is to the left of the decimal.
- Count the number of places the decimal was moved and use this number as your exponent.
- The exponent is positive if the decimal was moved to the left.
- The exponent is negative if the decimal was moved to the right.
- Example: 345000 is expressed as 3.45 X 105
How to expand numbers from scientific notation
- Add decimal places, with zeroes as place holders, to equal the number in the exponent.
- Move the decimal to the left if the exponent was negative.
- Move the decimal to the right if the exponent was positive.
- Example: 3.45 X 10-5 is 0.0000345
Addition and subtraction in scientific notation
- If the exponents are the same simply add/subtract the coefficients and keep the same exponent.
- If the exponents are different make them the same by moving the decimal of the smaller number to the left until the exponents match and then perform the operation.
- Remember that your final answer must have only one non-zero digit to the left of the decimal.
- Example: 3.0 X 103 + 4.0 X 102 = ?
Before beginning the numbers should be adjusted as such:
3.0 X 103 + 0.40 X 103 = 3.4 X 103
Multiplication and division in scientific notation
- To multiply – multiply the coefficients and add the exponents
- To divide – divide the coefficients and subtract the exponents
- Remember that your final answer must have only one non-zero digit to the left of the decimal.
- Example: 6.0 X 102 / 2.0 X 105 = ?
Divide the coefficients: 6.0 / 2.0 = 3.0
Subtract the exponents: 2 – 5 = -3
Final Answer: 3.0 X 10-3
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