Name: how mass differs from weight
Uploaded: 2023-09-22T11:49:39.000Z
Duration: 1 min 19 s
Channel: JoVE

Die Masse eines Objekts ist ein Maß für die Menge an Materie, die es enthält, und hängt von der Anzahl der Atome darin ab.
Sein Gewicht ist die Gravitationskraft, die von einem größeren Objekt wie der Erde oder dem Mond auf ihn wirkt, je nachdem, was ihm am nächsten liegt.
Da sich die Menge der Materie als Reaktion auf die ausgeübte Kraft nicht ändert, bleibt die Masse des Objekts konstant.
Sein Gewicht hängt jedoch von seinem Standort ab. Ein Objekt auf der Erde wiegt anders als das auf dem Mars oder dem Mond, aber seine Masse bleibt gleich. Die Gewichtsänderung ist auf den Beschleunigungsunterschied zurückzuführen, der durch die auf ihn einwirkende Schwerkraft entsteht.
Masse kann niemals Null sein, aber Gewicht wird Null, wenn die Gravitationskraft nicht auf sie einwirkt. Wendet man diese Beobachtung und das zweite Newtonsche Gesetz an, so wiegt ein Objekt mit der Masse m mal dem Vektor g.
Das heißt, je größer die Masse eines Objekts ist, desto größer ist sein Gewicht. Masse ist eine skalare Größe, aber Gewicht ist ein Vektor, der auf den Erdmittelpunkt gerichtet ist.

masse und gewicht

Masse und Gewicht werden in der Alltagssprache oft synonym verwendet. Zum Beispiel zeigen medizinische Aufzeichnungen oft unser Gewicht in Kilogramm an, jedoch nie in den richtigen Einheiten von Newton. In der Physik gibt es jedoch einen wichtigen Unterschied. Gewicht ist die Zugkraft der Erde auf einen Gegenstand. Es hängt von der Entfernung vom Zentrum der Erde ab. Das Gewicht variiert stark, wenn wir die Erdoberfläche verlassen, im Gegensatz zur Masse, die sich nicht mit dem Standort ändert. Auf dem Mond zum Beispiel beträgt die Gravitationsbeschleunigung nur 1,67 m/s² im Vergleich zu 9,8 m/s² auf der Erde. Daher hat eine Masse von 1,0 kg ein Gewicht von 9,8 N auf der Erde, aber nur etwa 1,7 N auf dem Mond. Die Masse eines Objekts ist jedoch auf der Erdoberfläche, in der Umlaufbahn oder auf der Oberfläche des Mondes gleich.

Wenn ein Objekt fallengelassen wird, beschleunigt es sich zum Zentrum der Erde. Das zweite newtonsche Gesetz besagt, dass eine resultierende Kraft auf ein Objekt für seine Beschleunigung verantwortlich ist. Wenn der Luftwiderstand als vernachlässigbar angesehen wird, entspricht die resultierende Kraft, die auf ein fallendes Objekt wirkt, der Gravitationskraft, die allgemein als Gewicht oder die Kraft auf ein Objekt mit der Masse 'm' aufgrund der Schwerkraft bekannt ist.

Beachten Sie, dass Gewicht und Masse, obwohl sie eng miteinander verbunden sind, unterschiedliche physikalische Größen sind. Masse ist eine intrinsische Eigenschaft eines Objekts; es ist eine Menge an Materie. Es ist verlockend, Masse mit Gewicht gleichzusetzen, da die meisten unserer Beispiele auf der Erde stattfinden, wo sich das Gewicht eines Objekts minimal mit dem Standort des Objekts auf der Erde ändert. Außerdem ist es schwierig, alle Atome und Moleküle in einem Objekt zu zählen und zu identifizieren, daher wird die Masse selten auf diese Weise bestimmt.

Dieser Text ist angepasst von <a href="https://openstax.org/books/university-physics-volume-1/pages/5-4-mass-and-weight">Openstax, University Physics Volume 1, Abschnitt 5.4: Masse und Gewicht.</a>

Masse und Gewicht

Masse und Gewicht werden im alltäglichen Gespräch oft synonym verwendet. Zum Beispiel zeigen Krankenakten oft unser Gewicht in Kilogramm, aber nie ...

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Mass and Weight

how mass differs from weight

Mass and weight are related, but they are not the same. Mass is the amount of matter in an object. Weight is the force of gravity acting on that object.

This difference matters because mass stays the same even when gravity changes. Weight can change if the gravitational pull changes. A person or object therefore has the same mass, but not always the same weight.

The terms are often used in everyday speech as if they mean the same thing. In physics, they describe two different ideas. Understanding both helps students read science problems and compare objects more accurately.

How Mass Differs from Weight

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Learn how mass and weight are different in physics. This K12 science video explains mass as matter and weight as the force of gravity on an object.

How Mass Differs from Weight | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

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How Mass Differs from Weight

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