![]() 12 inches/min Skill Sheet 3.2: Making Line Graphs Parts 1 through 2: There are no questions to answer in parts 1 through Graph of money earned vs. Sample problem: 28 m/sec km/hr mph seconds hours kilometers meters Sample problem: 63 mph mph miles 4. Part 6 answers:Ģ Skill Sheet 3.1: Speed Problems 1. A There are no questions to answer in Part ,000,, ,500,000,, Part 5 answers: There are no questions to answer in Part 5. By changing from quarts to liters, the beverage industry increases the amount of product it sells per bottle and can charge more money per bottle sold ounces 7. An additional 54 milliliters of beverage must be added to a quart equal one liter. 5,200 milliliters ,000 centimeters = 1 kilometer Skill Sheet 2.2: Converting Units Parts 1 to 3: There are no questions to answer in parts 1 to Answers are: Starting amount and unit Ending amount and unit 3.0 inches meter 3.7 gallons 14 liters 47.0 pounds 21.3 kilograms 3.0 pints 1.4 liters 230 grams 0.23 kilogram 42 millimeters 4.2 centimeters 1,000 millimeters 1 liter 24.3 meters kilometer gallons (Since, building codes are listed in ranges, 740 gallons is a precise enough answer.) m/sec grams 5. ![]() Information and illustrations of the inventions can be found using the Internet or library kilograms centimeters 5. Galileo's many inventions include the thermometer, water pump, military compass, microscope, telescope, and pendulum clock. Skill Sheet 2.1: International System of Units Parts 1 through 6: There are no questions to answer in parts 1 through 6. However, students may choose another invention as long as they provide valid reasons for their decision. Galileo's telescope is the most likely student response, because it so profoundly changed our understanding of the solar system. ![]() 18th floor seconds Skill Sheet 1.2: Galileo Galilei 1. uses a mere 1µPa as reference, so the two sound scales are not readily comparable.A measured level equal to its reference is 0dB in whatever scale you use, because the ratio is then 1, and as log-base-10(1) = 0, so 20log(1) = 0.Why can't you count from 0µPa? Because that makes the denominator 0, and you can't divide by 0.1 Skill Sheet 1.1: Solving Equations Part 1 through 5: There are no questions to answer in parts 1 through 5. (The standard abbreviation for 'micro' is the Greek letter µ.)Why 20µPa? It is the SPL of the faintest sound the fully-healthy human ear can detect - a staggeringly low 1/(5000 000 000) of Standard Atmospheric Pressure.So deciBels avoid clumsy calculations with lots of big exponents, and turns many of the sums into just adding and subtracting modest numbers.Therefore, measuring sound level in air, and without going into the derivation of the 20 constant, the SPL = deciBels.So to quote the sound pressure level fully, it is N dB re 20µPa.Marine acoustics - dolphin calls, sonar etc. It's an extremely tiny pressure, but still too big for acoustics, where you need to work in millionths of Pascals - i.e. ![]() It helps if know basic logarithm principles!The deciBel (dB) is not a measure of power or intensity of sound only, but can describe any acoustic, electrical or electromagnetic signal, so to use it properly you have to specify the right units and scale.Further, it is not a linear unit like a metre or a litre, but a product of a constant with the logarithm of a ratio! And that ratio's denominator is the reference levelrelevant to what you are measuring, and to which you compare the measured level.We use this logarithmic scale because the human ear is roughly logarithmic in response to sound pressure and the maximum pressure it can bear for a short time painfully but without injury is 1 million times the faintest it could hear before too many of those maxima hit it for too long.In measuring sound in air by deciBels, you use 20µPa (20 micro-Pascals), where the Pascal is the official SI unit of pressure. ![]() Most sound volumes figures are of Sound Pressure Level (SPL) in deciBels, and this is a brief explanation. LOL+++Many ways indeed! it's not a simple matter, and we have to distinguish between intensity and power, which are not the same things. Sound volume is often measured in decibels. ![]()
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