Name: si and customary measurement systems
Uploaded: 2023-09-22T11:49:19.000Z
Duration: 1 min 27 s
Channel: JoVE

La longitud, la masa y el tiempo son las cantidades base para la medición, y sus unidades se conocen como unidades base.
Las unidades derivadas de las unidades base se conocen como unidades derivadas.
Los sistemas de unidades se pueden clasificar en el Sistema Internacional de unidades o unidades SI y el sistema de unidades consuetudinario de los Estados Unidos.
En las unidades del SI, el metro, el kilogramo y el segundo son las unidades base, mientras que en el sistema habitual de unidades de EE. UU., el pie, la libra y el segundo son las unidades básicas.
Por ejemplo, la unidad de fuerza del SI es newton, que es una unidad derivada, se define como la fuerza necesaria para acelerar un kilogramo de masa a razón de un metro por segundo al cuadrado.
En el sistema consuetudinario de unidades de EE. UU., la unidad de masa es slug, que es una unidad derivada. Se define como la cantidad de materia acelerada en un pie por segundo al cuadrado cuando se actúa sobre ella con una fuerza de una libra.
Las unidades de un sistema se pueden convertir en las de otro sistema utilizando factores de conversión.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. págs. 7\u20128</li>
	<li>Cerveza, F.P.; Johnston, E.R.; Mazurek, D.F.; Cromwell, P.J. y Self, B.P. (2019). Mecánica vectorial para ingenieros: estática y dinámica. Nueva York: McGraw-Hill. págs. 4 y 8</li>
	<li>Meriam, J.L.; Kraige, L.G. y Bolton, J.N. (2020). Ingeniería Mecánica \u2012 Estática. Hoboken, Nueva Jersey: John Wiley. págs. 7 y 8</li>
</ol>

unidades de medida

Units of Measurement

La ingeniería mecánica es una de las ramas más antiguas de la ingeniería. Se ocupa del diseño, análisis y fabricación de máquinas y sistemas mecánicos. Para garantizar cálculos precisos y exactos, se utilizan unidades de medida. Estas proporcionan un sistema estándar para expresar y comparar cantidades físicas. Existen diversos sistemas de medidas históricos conocidos, como el sistema babilónico, el sistema romano, el sistema egipcio, el sistema olímpico, el sistema británico y el sistema del Valle del Indo. El Sistema Internacional de Unidades (SI) es el estándar de medida universalmente reconocido utilizado en ingeniería mecánica. Se basa en algunas unidades base fundamentales que se pueden combinar para expresar todas las demás cantidades físicas. Las unidades derivadas de las unidades base se conocen como unidades derivadas. Por ejemplo, la unidad SI de fuerza es el Newton, que es una unidad derivada. Se define como la fuerza requerida para acelerar un kilogramo de masa a una velocidad de un metro por segundo cuadrado. Existen diferentes sistemas de unidades de medida utilizados en todo el mundo. Además del Sistema Internacional de Unidades (SI), el Sistema de Unidades del Sistema Aduanero de los Estados Unidos es otro sistema comúnmente utilizado. En el sistema aduanero de los Estados Unidos, las unidades base son el pie, la libra y el segundo. La unidad de longitud es el pie, la unidad de masa es la libra y la unidad de tiempo es el segundo. En el sistema aduanero de los Estados Unidos, la unidad de masa es el slug, una unidad derivada. Se define como la cantidad de materia acelerada por un pie por segundo al cuadrado cuando se le aplica una fuerza de una libra. Dado que muchos países continúan utilizando el Sistema Aduanero de los Estados Unidos, también se ha desarrollado una relación entre las diferentes unidades comparables. Por ejemplo, un metro equivale a 3.280 pies. Las unidades derivadas también difieren de un conjunto de estándares a otro. Por ejemplo, el sistema SI utiliza el Newton como unidad de fuerza, pero el sistema aduanero de los Estados Unidos utiliza la libra. Las unidades de medida son esenciales en ingeniería mecánica porque permiten mediciones precisas y exactas. Los ingenieros utilizan estas unidades para diseñar y analizar máquinas y sistemas mecánicos, estimar cargas, tensiones y deformaciones en componentes mecánicos y predecir el comportamiento de las máquinas en diferentes condiciones de funcionamiento.

Unidades de Medida

La ingeniería mecánica es una de las ramas más antiguas de la ingeniería. Se ocupa del diseño, análisis y fabricación de máquinas ...

Education

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Introducción a la Estática

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si and customary measurement systems

Mechanical engineering depends on units of measurement for precise and accurate calculations. These units give engineers a standard way to express and compare physical quantities. They are essential when designing and analyzing machines and mechanical systems.

Many historical measurement systems have been used over time. Examples include the Babylonian system, the Roman system, the Egyptian system, the Olympian system, the British system, and the Indus Valley system. Today, the International System of Units, or SI, is the widely recognized standard used in mechanical engineering.

The SI system is built from base units. These base units can be combined to describe other physical quantities, which are called derived units. For example, the SI unit of force is the Newton. One Newton is the force needed to accelerate one kilogram of mass at one meter per second squared.

Another common system is the U.S. Customary System of Units. Its base units are the foot, the pound, and the second. In this system, length is measured in feet, mass is measured in pounds, and time is measured in seconds. The slug is the derived unit used for mass in this system, and it is defined by the amount of matter accelerated by one foot per second squared under a force of one pound.

Because many countries still use the U.S. Customary System, conversion relationships are important. For example, one meter equals 3,280 feet. Derived units also differ between systems. SI uses the Newton for force, while the U.S. Customary System uses the pound. Engineers use these units to estimate loads, stresses, and deformations, and to predict how machines behave under different operating conditions.

SI and Customary Measurement Systems

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SI and Customary Measurement Systems

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