Daily Science (August 27th) How many sig figs are in 1.0390? Round 59447 to two sig figs Write 7080000 in scientific notation Pull out your sig figs worksheet to check over

Metric Units pg. 13

SI Units SI units-a standard set of units scientists use to measure quantities Allows for consistency around the world Sig figs- conversions used in dimensional analysis and metric conversions have an infinite amount of sig figs and are not included when determining sig figs

SI Base Units Length Meter m Mass Gram g Volume Liter L Time Second s Measurement SI Base Unit Symbol of units Length Meter m Mass Gram g Volume Liter L Time Second s Temperature Kelvin K Amount of substance Mole mol Energy Joule J

SI Prefixes ***Write the prefix 1st then the base unit *** Factor Name Symbol 106 mega M 103 kilo k 101 Deca Da ----------- Base Unit m, L, sec, g 10-1 deci d 10-2 centi c 10-3 milli m 10-6 micro µ 10-9 nano n

Using the Number Line to Convert Btw. Prefixes

Dimensional Analysis A way to convert from one prefix or unit to another prefix or unit. Multiplying fractions

Steps for dimensional analysis 1. Start with what you are given (add a x and a fraction ) 2. Place the given unit on the bottom of your ‘fraction’ so it will cancel out. Then place the desired unit on top. 3. Place a 1 in front of the larger unit Place the value for the smaller unit in the empty space Use known relationships (i.e.12 in =1 ft) 4. multiply numbers on the top and divide numbers on the bottom of fraction Ex. how many cm in 1.5 m? 1.5 m x = cm 100 1 cm 150 m

Check yourself Smaller unit to bigger unit=smaller number bigger unit to smaller unit= bigger number

Example How many cm are in 1.3 Km? How many dL are in 3.4 mL? Convert 2.00 mile into inches. 1 mile=5,280 feet I am 883,008,000 seconds old. How old am I in years?