Name: measurement units, standards, and si basics
Uploaded: 2023-09-22T11:49:38.000Z
Duration: 1 min 10 s
Channel: JoVE

Eine physikalische Größe ist eine beliebige Zahl, die ein physikalisches Phänomen quantitativ beschreibt. Zum Beispiel ist die Länge eine physikalische Größe, die den Abstand zwischen zwei Punkten beschreibt.
Die Messungen physikalischer Größen werden in Einheiten ausgedrückt. Die Masse Ihres Körpers kann in Kilogramm und Ihre Körpergröße in Metern ausgedrückt werden.
Physikalische Größen, die ohne Standardeinheiten ausgedrückt werden, sind schwer zu verstehen. Wenn beispielsweise die Höhe des Eiffelturms mit 300 angegeben wird, ist der Kontext der Zahl unklar, ohne dass Einheiten angegeben werden. Das bedeutet, dass der Eiffelturm relativ hoch oder sehr klein sein kann.
Um die verschiedenen Eigenschaften der Materie genau zu messen und zu melden, wurde ein gemeinsames Messsystem entwickelt, das als Internationales Einheitensystem oder SI-Einheiten bekannt ist.
Das SI-System empfiehlt, sieben Basisgrößen und deren Einheiten zu verwenden, die das Internationale Mengensystem bilden.

maßeinheiten und -standards

Ein physikalische Größe wird entweder durch Angabe ihrer Messmethode definiert oder indem angegeben wird, wie sie aus anderen Messungen berechnet wird. Zum Beispiel könnte man bei einem metallischen Würfel seine Masse und Abmessungen durch Angabe von Methoden zur Messung definieren, wie beispielsweise die Verwendung einer Waage und eines Metermaßes. Dann könnte man das Volumen definieren, indem man sagt, dass es das Quadrat der Seitenlänge ist, und die Dichte könnte als die Masse geteilt durch das Volumen berechnet werden.

Messungen von physikalischen Größen werden in Einheiten ausgedrückt, die standardisierte Werte sind. Zum Beispiel kann die Länge der Seiten eines Würfels, die eine physikalische Größe ist, in Metern oder Zentimetern angegeben werden, abhängig von der Größe des Würfels.

Es gibt hauptsächlich zwei Einheitensysteme. Das erste ist das metrische System, das SI-Einheiten verwendet, und das zweite ist das übliche oder imperiale System, das englische Einheiten verwendet. SI ist die internationale Abkürzung für das französische Système International d'Unités (Internationales Einheitensystem). Es ist das weltweit am häufigsten verwendete Einheitensystem und wird von Wissenschaftlern und Mathematikern als das Standard-System betrachtet.

Dieser Text ist angepasst von <a href="https://openstax.org/books/university-physics-volume-1/pages/1-2-units-and-standards">Openstax, University Physics Volume 1, Abschnitt 1.2: Einheiten und Standards.</a>

Maßeinheiten und -standards

Eine physikalische Größe wird entweder durch die Angabe ihrer Messmethode oder durch die Angabe der Art und Weise, wie sie aus anderen Messungen berechnet wird, definiert. Zum Beispiel...

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Physics Basics

Grundlagen der Physik

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Units and Standards of Measurement

measurement units, standards, and si basics

Measurement units, standards, and SI basics help scientists describe physical quantities clearly. A unit gives a number meaning, while a standard provides a fixed reference for that measurement. Together, they make results easier to compare and understand.

The International System of Units, or SI, is the most common measurement system in science. It uses agreed-upon base units for common quantities. These standards reduce confusion when measurements are shared across labs, classrooms, and countries.

Using the same units and standards also makes data more reliable. It allows students and scientists to compare measurements and communicate results with less error. This foundation is essential for accurate work in physics, chemistry, and other sciences.

Measurement Units, Standards, and SI Basics

measurement-units-standards-and-si-basics

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units and standards of measurement

Measurement units, standards, and SI basics help scientists describe physical quantities clearly. A unit gives a number meaning, while a standard provides a fixed reference for that measurement. Together, they make results easier to compare and understand. The International System of Units, or SI, is the most common measurement system in science. It uses agreed-upon base units for common quantities. These standards reduce confusion when measurements are shared across labs, classrooms, and...

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Learn how measurement units, standards, and the SI system give physical quantities clear meaning and make scientific results easier to compare.

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Measurement Units, Standards, and SI Basics

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