Presentation on theme: "Using Scientific Notation Scientific Notation is a way of expressing a value as the product of a number between 1 and 10 and a power of 10. Scientific."— Presentation transcript:
Using Scientific Notation Scientific Notation is a way of expressing a value as the product of a number between 1 and 10 and a power of 10. Scientific Notation makes very large or very small numbers easier to work with.
Example: The number 300,000,000 written in scientific notation is 3.0x10 8. The exponent, 8, tells you that the decimal point is really 8 places to the right of the 3. Example: The number 0.00086 written in scientific notation is 8.6x10 -4. The negative exponent, -4, tell you that the decimal point is really 4 places to the left of the 8.6.
When multiplying numbers written in scientific notation, you multiply the numbers that appear before the multiplication signs and add the exponents. When dividing numbers written in scientific notation, you divide the numbers that appears before the exponential terms and subtract the exponents.
International System of Units SI is built upon seven metric units, known as Base Units. › Example: The base unit for length(L) is the meter (m). Additional SI units, called Derived Units, are from combinations of base units. › Example: The derived unit for volume (V) is cubic meters (m 3 ).
QuantityUnitSymbol LengthMeterM MassKilogramKg TemperatureKelvinK TimeSecondS Amount of substanceMoleMol Electric currentAmpereA Luminous intensityCandelacd
QuantityUnitSymbol AreaSquare meterM2M2 VolumeCubic meterM3M3 DensityKilograms per cubic meter Kg/m 3 PressurePascal (kg/mxs 2 )Pa EnergyJoule (kgxm 2 /s 2 )J FrequencyHertz (1/s)Hz Electric ChargeCoulomb (Axs)C
PrefixSymbolMeaningMultiply Unit by Giga-GBillion1,000,000,000 Mega-MMillion1,000,000 Kilo-kThousand1,000 Deci-dTenth0.1 Centi-cHundreth0.01 Milli-mThousandth0.001 Micro-µMillionth0.000001 Nano-nBillionth0.000000001
A conversion factor is a ratio of equivalent measurements that is used to convert a quantity expressed in one unit to another unit. Example: Convert the height of Mt. Everest, 8848 meters, into kilometers. kilo- =1000 8848m X 1km = 8.848km 1000m
Precision is a gauge of how exact a measurement is. Precision of a calculated answer is limited by the least precise measurement used in the calculation. Accuracy is the closeness of a measurement to the actual value of what is being measured.
Significant figures are all the digits that are known is a measurement, plus the last digit that is estimated. › Example: On an analog clock it may take you 5 minutes to eat a sandwich. On a digital clock it may take you 5.25 minutes to eat a sandwich. The time recorded as 5.25 minutes has three significant figures. The time recorded as 5 minutes has one significant figure. The fewer the significant figures, the less precise the measurement.
Measuring Temperature A thermometer is an instrument that measures temperature, or how hot an object is. The two temperature scales that you are probably most familiar with are the Fahrenheit scale and the Celsius scale. Fahrenheit: water freezes at 32 degrees Celsius: water freezes at 0 degrees Conversion: ºC = 5 (ºF – 32.0º) or ºF = 9 (ºC) +32.0º 9 5
SI unit for temperature is kelvin (K). Conversion: K = ºC + 273