Question of The Day

The primary purpose of the passage is to

Measurement ranks as one of our oldest skills. Many of the questions people ask every day begin with "How many?" or "How much?" A person may ask a friend, "How many brothers and sisters do you have?" or, "How much do you weigh?" The answers to both questions use numbers. But the first question is answered by counting, and the second by measuring. Each child in a family is a whole person and must be counted, not measured. But a persons weight must be measured, and this is done by standing on a scale. Almost everyone uses measurement daily. The food we eat, the clothes we wear, the work we do, and many of the games we play involve measurement. For example, shoppers buy meat by the kilogram and cloth by the meter. Many workers are paid by the hour. An athlete who runs 100 meters in the shortest time wins the race. People also use measurement to help them understand one another and to work together easily. A boy could write to someone living far away and describe himself as tall and heavy. But it would be better if he described himself as 137 centimeters tall and weighing 40 kilograms. In the same way, a carpenter building a house can order a door that measures 76 centimeters wide and know it will fit the opening allowed for it. Every measurement involves two things: (1) a number and (2) a unit. A number by itself is not a measurement. There would be no point in saying that a stick has a length of 6. No one would know whether the stick was 6 centimeters or 6 meters long. But if someone described the stick as being 6 centimeters long, then the measurement would have meaning. There are two major systems of measurement: (1) the imperial system and (2) the metric system. The measurement units in each system are related to one another. The imperial system of measurement started in about the 1200s, though its units may be traced back even earlier. Most nations--and all scientists--use the metric system. The official name of this system is the Systeme International dUnites (International System of Units). To make accurate measurements, people have invented such measuring tools as clocks, scales, tape measures, thermometers, and other devices. Measurement with tools involves comparing the object or event being measured with the units marked on the tool. For example, a ruler placed beside a pencil shows the number of centimeters and millimeters equal to the length of the pencil. Most measurements involve reading some kind of scale. The problem is that no matter how many subdivisions the scale has, the object being measured is likely to fall between two of them. As a result, every measurement can only be an approximation. A measurement may come close, but it never matches the scale perfectly. Without a magnifying lens, for example, a ruler is accurate only to within a half millimeter. But simple measurements within a fiftieth of a millimeter can be made with an instrument called a micrometer caliper. Measuring tools include a wide variety of devices. Gauges and meters measure such items as liters of petrol or cubic meters of natural gas. A kilowatt-hour meter measures electricity. A speedometer measures the speed of a car or other vehicle, and an odometer records the distance traveled by the vehicle. Other devices measure the volume of such substances as petroleum in barrels.

briefly explain the importance, function, systems and types of measurements that are used in everyday life.