Warm UP How many seconds are there in a day? How many total pins are knocked down if you bowl a turkey (3 strikes)? How many pennies would you need to have 6 dollars total?

Unit Conversion Factor Dimensional Analysis

How many seconds are there in a day? First assess what you know: There are 60 seconds in a minute There are 60 minutes in an hour There are 24 hours in a day Cancel Units and Solve the Problem: 60 seconds x 60 minutes x 24 hours 1 minute 1 hour 1 day = 86400 seconds 1 day

Important Notes In dimensional analysis we use a line to separate two things that are equal 1 day = 24 hours IS THE SAME AS… _1 day__ OR 24 hours 24 hours 1 day We multiply numbers on the top and divide by any numbers on the bottom (BUT UNITS MUST BE CORRECT IN THE ANSWER!!!) Units are very important, you will lose points if you forget them!

For Example In the previous problem… 60 seconds x 60 minutes x 24 hours 1 minute 1 hour 1 day (60 x 60 x 24) = 86,400 s/day

How many total pins are knocked down if you bowl a turkey? First assess what you know: There are 10 pins knocked down in a strike There are 3 strikes in a turkey Then write out the problem and cancel units: 1 Strike x 1 Turkey = 1 Turkey 10 pins 3 Strikes 30 pins Is this the answer you want? No – Invert your answer ANSWER: 30 Pins knocked down/Turkey

How many pennies would you need to have 6 dollars total? First assess what you know: There are 100 pennies in a dollar You need 6 dollars Then write out the problem and cancel units: 100 pennies x 6 dollars = 600 pennies 1 dollar

Let’s Practice… A new drug has a dosage of 2.3 mL for every 1 pound of patient’s body weight. If you have a patient who weights 198 lbs, how much drug should you give them?

Show Your Work! 2.3 mL X 198 lbs = 1 lb Pounds cancel out and we are left with: 2.3 mL X 198 = 455.4 mL

One More Important One… If the STEELERS beat the Cowboys this season by three touchdowns (including extra points) and three field goals, how many total points will the Steelers WIN by?

Show Your Work: First assess what you know: There are 7 points per touchdown There are 3 total touchdowns There are also 3 field goals There are 3 points per field goal Then write out the problem and cancel units: 7 points x 3 touchdowns = 21 points 1 touchdown 3 points x 3 field goals = 9 points 1 field goal 21 points + 9 points = 30 points

SI Units: Length Volume Mass Temperature Time Pressure Energy Amount of a Substance Luminous Intensity Electric Current Meters (m) Liters (L) Kilograms (kg) Kelvin (K) Seconds (s) Pascals (Pa) Joules (J) Moles (mol) Candela (cd) Ampere (A)