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2-B. Section 2B. Standardized Units Pages 101-112. 2-B. Standardized Unit Systems. Metric system (SI) Syst è me International U.S. customary system (USCS) Roots from ancient Middle Eastern civilizations. Unit conversions within systems. Unit conversions between systems. 2-B.
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2-B Section 2B Standardized Units Pages 101-112
2-B Standardized Unit Systems • Metric system (SI) • Système International • U.S. customary system (USCS) • Roots from ancient Middle Eastern civilizations Unit conversions within systems. Unit conversions between systems.
2-B U.S. Customary System - Lengths page101
2-B U.S. Customary System - Weights page102
2-B U.S. Customary System - Volumes page102
2-B Conversions within USCS Ex1/103 In the Kentucky Derby, horses race 10 furlongs. How many miles is this?
2-B Conversions within USCS Ex1/103 In 20,000 Leagues Under the Sea, does the title refer to an ocean depth? [convert marine leagues to miles]
Conversions within USCS 51’/114 If 150 bushels of wheat are traded on one day, how many cubic inches are traded? how many cubic feet?
2-B International Metric System • Invented in France, late 18th century • Replace many customary units with a few basic units • Simplify conversions by using a base 10 system
2-B International Metric System • The basic units are: • meter (m) for length • gram (g) for mass • second (s) for time • liter (L) for volume
2-B Metric System - Prefixes 5.23 m 523 cm .00523 km
2-B Conversions within Metric System • Convert 19 decimeters to millimeters: • conversion or decimal movement: • 1900 millimeters • Convert 1378 g to kg: • conversion or decimal movement: • 1.378 kg
Conversions between Metric and USCS 60*/114 Convert 1550 millimeters to yards. 63/114 Convert 45 liters to gallons. 65/114 Convert 8550 square feet to square meters. 67/114 Convert 10 kilograms per cubic meter to pounds per cubic foot.
More Practice 103/117 You see oranges in an Italian market priced at 0.8 euro per kilogram. What is the price in dollars per pound? 105/117 A French car manufacturer claims that its newest economy model has gas “mileage” of 20 kilometers per liter. What is the gas mileage in miles per gallon?
2-B Homework 2B – Part I Pages 113-117 #48,50,60,62,68,104,106
2-B Temperature Units • Fahrenheit (US) • Water freezes at 32ºF, boils at 212ºF • Celsius (International) • Water freezes at 0ºC, boils at 100ºC • Kelvin (Scientific) • Water freezes at 273.15K, boils at 373.15K • Coldest known temperature = 0 Kelvin (-459.67ºF = -273.15ºC)
2-B Converting Temperatures (page107)
2-B Example Ex6/108 A ‘normal’ human temperature is 98.6ºF What is that in Celsius and Kelvin? 98.6o F = 37o C = 310.15o K
2-B Energy and Power • Energy is what makes matter move or heat up. The international unit of energy is the joule. • Power is therateat which energy is used. The international metric unit of power is the watt, defined as • A kilowatt-hour is a unit of energy and 1 kWh = 3600000 joules = 3.6 million joules 1 kw x 1hr = 1000j/s x 60s/m x 60m/hr x 1 hr
2-B 93/116 Your refrigerator uses an average power of 350 watts, and your utility company charges 10 cents per kilowatt-hour of energy. How much does it cost to run your refrigerator for a year? Conversion:350 watts is .350 kilowatts (why?)Usage per year in kilowatt-hours: .350 kilowatts x 24 hours/ 1 day x 365 days/1 year = 3066 kilowatt-hours / yearCost per year: 3066 kilowatt-hours / year x .10 $ / 1 kilowatt-hour = 306.60 $ per year
2-B Units of Density/Concentration • Density (e.g.material, population)– describes compactness or crowding. • material: mass/volume (g/cm3) • Population: people/mi2 • Concentration(e.g. pollutants, BAC) describes the amount of one substance mixed with another. • pollutants: ppm • BAC: g/100mL (legal limit is 0.08g/100mL)
2-B Example Ex9/111-2 Manhattan Island has a population of ≈ 1.5 million people living in an area of about 57 km2. What is its population density? How much space is available per person?
2-B Example (for fun) Ex9/111-2(cont.) How much space is that per person? Which is roughly 6m×6m, or 20 ft × 20 ft
2-B Example Ex10/112 An average-sized man has about 5L of blood, and an average 12-ounce beer contains 15g of alcohol. If all the alcohol were immediately absorbed into the bloodstream, what would his BAC be?
More Practice 79/114 The land area of the US is about 3.5 million square miles, and the population is about 280 million people. What is the average population density? 83/114 A typical glass of wine contains about 20 grams of alcohol. Consider a 110-pound woman, with approximately 4 liters of blood who drinks two glasses of wine. Assuming immediate absorption, what is her BAC?
2-B Homework 2B – Part II Pages 113-117 #70, #72, #80, #84, #94