English vs Metric Combating Measurement Systems Accuracy Precision

English vs. Metric Combating Measurement Systems

Accuracy, Precision, and Error Accuracy and Precision Accuracy is a measure of how close a measurement comes to the actual or true value of whatever is measured. Precision is a measure of how close a series of measurements are to one another. To evaluate the accuracy of a measurement, the measured value must be compared to the correct value. To evaluate the precision of a measurement, you must compare the values of two or more repeated measurements.

Accuracy, Precision, and Error

Origins of the English System Grew out of the creative ways that people measured for themselves. Based on familiar objects or body parts that were used to take measurements . For Example: Short distances were measured on the ground by foot (feet) Longer distances measure by paces (a “mile” was 1, 000 paces) Capacity was measured using items like cups, pails, or baskets.

Origins Continued. . . These measurements lead to inconsistency when measuring the same items. Eventually a standard was set, so that measurements were consistent.

The Metric System Decimalized units of measurement originating in France in the 1790’s. Since the mid-1960’s the “SI” (International System of Units) has been the recognized system of measurement. Created to eliminate the conversion factors utilized in the English system of measurement. For Example : The standard measurement for distance is the meter. Everything is measured in meters, thousandths of meters, thousands of meters, etc.

Standard Metric Units Length/Distance : METER Volume/Capacity: CUBIC METER Weight: GRAM Fluid Measurement: Temperature: LITER CELCIUS

Converting between Systems When converting between the two systems of measurement, please be sure to multiply by the factors above.

Converting between Metric

Ways to Remember… King Henry Died Unexpectedly Drinking Chocolate Milk My Car Drives Backwards Down Highway K

Practice! 100 L = ml 50 hg = G 5 kl = ml 68, 000 mg = 17 cm = g km