To help students explore the metric system, they participate in a series of activities designed to introduce and build knowledge: How does basing a measurement system based the on number 10 make using the system more efficient? Have students view slide 5 of the Metric System Presentation to illustrate the power of 10 and preview metric unit prefixes.
Since the s, the International System of Units has been internationally agreed upon as the standard metric system.
The SI base units are based on physical standards. The definitions of the SI base units have been and continue to be modified and new base units added as advancements in science are made. Each SI base unit except the kilogram is described by stable properties of the universe. Although we often use mass and weight interchangeably, each one has a specific definition and usage.
The mass amount of matter of an object remains the same regardless of where the object is placed. For example, moving a brick to the moon does not cause any matter in it to disappear or be removed.
We call this force of attraction, the force of gravity. The gravitational pull on the object varies depending on where the object is with respect to the Earth or other gravity-producing object.
For example, a man who weighs pounds on Earth would weigh only pounds if he were in a stationary position, miles above the Earth's surface. This same man would weigh only pounds on the moon because the moon's gravity is only one-sixth that of Earth. The mass of this man, however, would be the same in each situation because the amount of matter in him is constant.
We measure weight with a scale, which is a spring that compresses when an object is placed on it.
If the gravitational pull is less, the spring compresses less and the scale shows less weight. We measure mass with a balance.
A balance compares the unknown mass to known masses by balancing them on a lever. If we take our balance and known masses to the moon, an object will have the same measured mass that it had on the Earth. The weight, of course, would be different on the moon.
Consistency requires that scientists use mass and not weight in its measurements of the amount of matter. The basic unit of mass in the International System of Units is the kilogram. A gram is a relatively small amount of mass and so larger masses are often expressed in kilograms.
When very tiny amounts of matter are measured, we often use milligrams which are equal to gram. There are numerous larger, smaller, and intermediate mass units that may also be appropriate.
At the end of the century, a kilogram was the mass of a cubic decimeter of water. Ina new international prototype of the kilogram was made of a platinum-iridium alloy.country in the world that does not use the metric system as its predominant system of measurement.
Most Americans think that our involvement with metric measurement is relatively new.
In fact, the United States has been increasing its use of metric rest of the world in the use of the metric system of measurement. The study found that. In this lesson, students are introduced to the metric system and practice using the metric system to measure many different quantities.
Because the metric system is the language of measurement for scientific practice world wide (almost!), learning this system is important for understanding and participating in global science practice. metric units.
STUDY. PLAY. the primary system of measurement used by most countries in the world; the modern metric system of measurement; abbreviated SI. International System of Units. a metric unit of length. meter. a system of measurement based on the number ten.
metric system. 2. METRIC SYSTEM 2. VOLUME The basic unit of volume in the metric system is the liter (1). The most common derived unit is the milliliter (ml) (10~3 or 1/ of a liter).
The metric system is the primary system of measurement used through much of the world and in science.
Each type of measurement has a base unit to which . The system of weights and measures is the collection of units and how they relate to each other. Example of The majority of the world uses the metric system: CENTIMETER The measurement most often used for length was the vara. It was a wood stick that measured between 32 and 35 inches.