Name: hydraulic force transfer with pascal's law
Uploaded: 2023-04-30T11:04:28.000Z
Duration: 1 min 3 s
Channel: JoVE

K12 Standards

Alabama Course of Study Science

9-12

Physics

motion-and-stability-forces-and-interactions

Motion and Stability: Forces and Interactions

9-12.P.1.4.b

Application of Pascal's Law

Hydraulische Systeme wie der hydraulische Wagenheber basieren auf dem Pascalschen Gesetz.
Es besteht aus einem U-förmigen Rohr mit Säulen mit ungleichem Querschnitt. Kolben A ist auf die kleinere Säule montiert, während Kolben B auf die größere Säule montiert ist.
Das Rohr wird mit einer Flüssigkeit gefüllt, so dass es in beiden Säulen die gleiche Höhe erreicht. Wenn eine Kraft auf den Kolben A ausgeübt wird, übt sie einen Druck p1 auf das Fluid aus.
Nach dem Pascalschen Gesetz wird dieser Druck durch die Flüssigkeit auf den Kolben B übertragen, wodurch der Kolben B nach außen gedrückt wird.
Der vom Kolben B empfundene Druck p2 ist gleich p1. Unter Verwendung des Verhältnisses zwischen Druck und Kraft erhält man nun einen Ausdruck für die Kräfte in einem hydraulischen System, vorausgesetzt, dass die Reibung im System vernachlässigbar ist. Die Abtriebskraft kann im Hydrauliksystem erhöht werden, indem eine Kraft auf eine kleinere Fläche ausgeübt wird.

anwendung des pascal'schen gesetzes

Pascals experimentell nachgewiesene Beobachtungen - dass eine Änderung des Drucks, der auf eine abgeschlossene Flüssigkeit ausgeübt wird, unvermindert durch die Flüssigkeit und an die Wände ihres Behälters übertragen wird - bilden die Grundlage für die Hydraulik, eine der wichtigsten Entwicklungen in der modernen mechanischen Technologie.

Hydraulische Systeme werden zur Betätigung von Automobilbremsen, hydraulischen Wagenhebern und zahlreichen anderen mechanischen Systemen verwendet. Wir können eine Beziehung zwischen den Kräften in einem einfachen hydraulischen System ableiten, indem wir das Pascal'sche Prinzip anwenden. In dem System gibt es zwei Kolben auf gleicher Höhe, daher gibt es keinen Druckunterschied aufgrund eines Unterschieds in der Tiefe. Der Druck aufgrund der auf die kleinere Fläche wirkenden Kraft wird unvermindert durch die Flüssigkeit und an alle Wände des Behälters übertragen. Somit ist der Druck, den der größere Kolben spürt, gleich dem Druck, der von der kleineren Fläche übertragen wird. Dies liefert eine Gleichung, die das Verhältnis von Kraft zu Fläche in jedem hydraulischen System beschreibt, vorausgesetzt, die Kolben befinden sich auf gleicher vertikaler Höhe und die Reibung im System ist vernachlässigbar. Hydraulische Systeme können die auf sie ausgeübte Kraft erhöhen oder verringern. Um die Kraft zu erhöhen, wird der Druck auf eine größere Fläche ausgeübt. Wenn zum Beispiel eine Kraft von 100 N auf den kleineren Zylinder ausgeübt wird und der andere Zylinder eine fünfmal größere Fläche hat, beträgt die Ausgangskraft 500 N.

Der hydraulische Wagenheber ist solch ein hydraulisches System. Er wird zum Anheben schwerer Lasten verwendet, wie sie von Kfz-Mechanikern zum Anheben eines Autos verwendet werden. Eine kleine Kraft, die auf eine kleine Fläche ausgeübt wird, kann eine viel größere Kraft auf der anderen Seite über eine größere Fläche ausgleichen. Aus dem Pascal'schen Prinzip lässt sich zeigen, dass die zur Anhebung eines Autos erforderliche Kraft geringer ist als das Gewicht des Autos.

Dieser Text ist angepasst von <a href="https://openstax.org/books/university-physics-volume-1/pages/14-3-pascals-principle-and-hydraulics">Openstax, University Physics Volume 1, Abschnitt 14.3: Pascal'sches Prinzip und Hydraulik.</a>

Anwendung des Pascal'schen Gesetzes

Pascals experimentell bewiesene Beobachtungen – dass eine Druckänderung, die auf ein eingeschlossenes Fluid ausgeübt wird, unvermindert über die gesamte ...

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hydraulic force transfer with pascal's law

Hydraulic force transfer uses Pascal's law to move pressure through an enclosed fluid. Pascal showed experimentally that a change in pressure applied to a confined fluid is transmitted undiminished throughout the fluid and to the walls of its container. That idea is the basis of hydraulics, a major part of modern mechanical technology.

Hydraulic systems appear in automotive brakes, hydraulic jacks, and many other machines. A simple hydraulic system uses two pistons at the same height. Because the pistons are at the same vertical level, there is no pressure change from depth. The pressure created by the force on the smaller area travels through the fluid and reaches the larger piston with the same value.

This pressure balance gives a relationship between force and area in a hydraulic system. It works when the pistons are at the same height and friction in the system is negligible. Hydraulic systems can increase or decrease the force applied to them. To increase the output force, the pressure is applied over a larger area.

For example, if a 100 N force is applied to the smaller cylinder and the other cylinder has five times the area, the output force is 500 N. A hydraulic jack uses this principle to lift heavy loads. Auto mechanics use hydraulic jacks to raise cars. A small force over a small area can balance a much larger force on the other side over a larger area. From Pascal's principle, the force needed to lift a car is less than the car's weight.

Hydraulic Force Transfer with Pascal's Law

hydraulic-force-transfer-with-pascals-law

characteristics of fluids

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application of pascal's law

Hydraulic force transfer uses Pascal's law to move pressure through an enclosed fluid. Pascal showed experimentally that a change in pressure applied to a confined fluid is transmitted undiminished throughout the fluid and to the walls of its container. That idea is the basis of hydraulics, a major part of modern mechanical technology. Hydraulic systems appear in automotive brakes, hydraulic jacks, and many other machines. A simple hydraulic system uses two pistons at the same height. Because...

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key terms and concepts

See how Pascal's law explains hydraulic force transfer in brakes and jacks, with pressure passing through a fluid and changing force through area.

Hydraulic Force Transfer with Pascal's Law | JoVE K12

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Hydraulic Force Transfer with Pascal's Law

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