Measurements, units English

Dimension measured Metric unit English unit Conversion factor F... 

FOOTLAMBERT (fL). A unit of luminance. One lumen per square foot leaves a surface whose luminance is 1 footlambert in all airections within a hemisphere. (If luminance is measured in English units, the candela per square inch is preferred. However, use of the SI unit, the candela per square meter, is generally accepted.)... 

It is important to know that all the questions are based on real numbers. In terms of measurement, units of measure are used from both the English and metric systems. Although conversion will be given between English and metric systems when needed, simple conversions will not be given. (Examples of simple conversions are minutes to hours or centimeters to millimeters.)... 

To measure Divisions Symbol Numerical expression Parts of basic unit English equivalent... 

While that equation has internally consistent units (English system), the variables are not normally measured in those units. Another disadvantage is that one must check graphs of the exponent and friction factor versus the Reynolds number to use the equation. 

In a chemistry laboratory, the metric system of measurement is used rather than the more familiar English system. The most common measurement unit for mass is the gram, not the pound. The most common measurement unit for volume is the milliliter, not the cup. One milliliter of water is a little more than half a tablespoon of water. One milliliter (abbreviated mL ) of water weighs approximately one gram (abbreviated g ). 

On December 11, 1998, NASA launched the 125-million-dollar Mars Climate Orbiter, which was intended to be the Red Planet s first weather satellite. After a 416-miIIion-mile (mi) journey, the spacecraft was supposed to go into Mars s orbit on September 23, 1999. Instead, it entered Mars s atmosphere about 100 km (62 mi) lower than plaimed and was destroyed by heat. Mission controllers later determined that the spacecraft was lost because English measurement units were not converted to metric units in the navigation software. 

The density of a substance is its weight per unit of volume. The unit of volume in the English system of measurement is 1 cubic foot or 1 f. To find the density of a substance, you must know its weight and volume. You then divide its weight by its volume to find the weight per unit volume. 

Ratio between the volumes, measured at standard conditions, of the gas and oil produced simultaneously (units m /m or cu.ft./barrel). The English acronym GOR is also used in France. 

The unit of land measure in the English system is the acre, while that in the metric system is the hectare. An acre is 4.356 X 104 ft2. A hectare is ten thousand square meters. The town of Willington in Connecticut requires a minimum area of 2.0 acres of land for a single-family dwelling. How many hectares are required ... 

Wall Assembly Construction. Because the materials and the design of the assemblies were specified in English units of measurement (for example 2 by 4 lumber, 24 in. on center), dimensions are expressed in English units with SI equivalents. By contrast, our equipment is calibrated in SI units, and consequently SI units are used in the remaining sections of this paper. 

Sometimes it is necessary to convert from a measurement in the English system to a measurement in the SI system. (The English system is sometimes referred to as the U.S. Customary system of units.) There are numerous SI/English conversions. Consult your book and check with your instructor to see which they recommend. We will be using the following in many of our examples ... 

Meter a unit of measurement of length in the metric system. One meter equals approximately 39.37 inches in the English system. 

In this chapter, I offer suggestions on how to choose the unit or units and then how to work with the unit or units you ve chosen. This chapter also covers the tricky conversions of square feet to square inches or cubic yards to cubic feet. And, of course, no discussion of units is complete without introducing meters and kilograms, so you get conversions involving metric and English measures. 

You ve decided to go to Europe and you want to be sure that you order the right size beverage, know how far you ll be traveling by car, and dress appropriately for the weather on any particular day. All these functions relate to changing from English units of measure to metric measure. Here are some of the more useful conversion equivalences you ll need for your travels. For help with the temperatures, refer to Chapter 10 for conversions from Celsius to Fahrenheit and back again. 

We will now summarize the conclusion of the Kirkwood-Bethe theory. Fig 15 shows the computed peak pressure and computed reduced tunc constant for TNT plotted VS the inverse reduced distance. The dotted lines are a power function fit thru the computed peak pressures. The x s are drawn in by the writer to compare computed and measured reduced time constants (taken from Fig 7.9, p 240 of Ref 1). Comparison of other computed and measured shock parameters on the basis of the power functions shown below (in Cole s notation and in English units) is made in Table 11 (from p 242 of Ref 1)... 

Write the units In 1999, the 125 million Mars Climate Orbiter spacecraft was lost when it entered the Martian atmosphere 100 km lower than planned. The navigation error would have been avoided if people had labeled their units of measurement. Engineers who built the spacecraft calculated thrust in the English unit, pounds of force. Jet Propulsion Laboratory engineers thought they were receiving the information in the metric unit, newtons. Nobody caught the error. 

Table 4-2 shows how some of the basic metric units are related to units commonly used in English-speaking countries for nonscientitle measurements. Although the United States, Great Britain, and Canada have officially resolved to convert to the metric system, it will be many years before the conversion is complete. In the meantime, you must learn to convert from one system to the other. The three conversion factors given in Table 4-2 (rounded off to 2.54... 

All systems of measurement / V I are based on arbitrary standards. The SI system is as arbitrary as the English system, but the relationship of one unit to another is more systematic and easier to remember in the metric system. 

Reports on the thermochemistry of propints are numerous but widely scattered. The distinction between gun propints and rocket propints must here be kept in mind. The use of the English units of measurement is still firmly entrenched, but as the impact of a change to the SI system on the numerical values will be slight, this change is to be expected soon... 

The terms of Eq. (14-128) are in English units and are explained in the Nomenclature. The exponent n is calculated from Eq. (14-84). Equation (14-128) is based on transition data obtained from orifice jetting measurements for the air-water system and on entrainment minimum data for some hydrocarbon systems. 

Chemistry and physics are experimental sciences, based on measurements. Our characterization of molecules (and of everything else in the universe) rests on observable physical quantities, expressed in units that ideally would be precise, convenient and reproducible. These three requirements have always produced trade-offs. For example, the English unit of length inch was defined to be the length of three barleycorns laid end to end—a convenient and somewhat reproducible standard for an agricultural society. When the metric system was developed in the 1790s, the meter was defined to be... 

Water hardness was important long before modern methods of measuring it were established and for this reason it is reported in rather parochial ways. Thus the English system records it as grains of calcium carbonate per litre, and this Medieval unit of weight is 65 mg. The Ameri-... 

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