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

Una cantidad física es cualquier número que describe un fenómeno físico cuantitativamente. Por ejemplo, la longitud es una cantidad física que describe la distancia entre dos puntos.
Las medidas de las cantidades físicas se expresan en términos de unidades. La masa de tu cuerpo se puede expresar en kilogramos y tu altura en metros de altura.
Las cantidades físicas expresadas sin unidades estándar son difíciles de entender. Por ejemplo, si se informa que la altura de la Torre Eiffel es de 300, sin proporcionar unidades, el contexto del número no está claro. Esto significa que la torre Eiffel podría ser relativamente alta o muy baja.
Con el fin de medir e informar con precisión sobre las diversas propiedades de la materia, se ha desarrollado un sistema común de medición conocido como el Sistema Internacional de Unidades o las unidades SI.
El sistema SI recomienda utilizar siete cantidades base y sus unidades, que forman el Sistema Internacional de Cantidades.

unidades y patrones de medida

Units and Standards of Measurement

Una cantidad física se define ya sea especificando su método de medición o indicando cómo se calcula a partir de otras medidas. Por ejemplo, consideremos un cubo metálico. Podríamos definir su masa y dimensiones especificando los métodos para medirlas, cómo usar una balanza y un metro. Luego, podríamos definir el volumen indicando que es el cubo de su lado, y podríamos calcular la densidad dividiendo la masa por el volumen. Las mediciones de cantidades físicas se expresan en términos de unidades, que son valores estandarizados. Por ejemplo, la longitud del lado de un cubo, que es una cantidad física, se puede expresar en unidades de metros o centímetros, dependiendo del tamaño del cubo. Principalmente se utilizan dos sistemas de unidades. El primero es el sistema métrico, que utiliza unidades del SI, y el segundo es el sistema habitual o imperial, que utiliza unidades inglesas. SI es la abreviatura internacional del Sistema Internacional de Unidades Francés. Es el sistema de unidades más utilizado a nivel mundial y se considera el sistema estándar por científicos y matemáticos. Este texto está adaptado de <a href="https://openstax.org/books/university-physics-volume-1/pages/1-2-units-and-standards">Openstax, University Physics Volume 1, Section 1.2: Units and Standards.</a>

Unidades y Patrones de Medida

Una magnitud física se define especificando su método de medición o indicando cómo se calcula a partir de otras mediciones. Por ejemplo...

Education

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Unit 1

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Physics Basics

Conceptos básicos de física

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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

introduction to scalers

Scalar Quantities in Physics

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vector or cross product

Cross Product of Two Vectors

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introduction to vectors

Vectors in Motion and Direction

Vectors describe quantities that have both size and direction. They are used in physics to show how motion, force, and other quantities act in space. A vector can be represented with an arrow. The length of the arrow shows the size, and the arrowhead shows the direction. This makes vectors useful for comparing how one quantity points relative to another. Scalars are different because they have size only and no direction. Understanding the difference between vectors and scalars is an important...

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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Measurement Errors, Accuracy, and Precision

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rules of significant figures

Counting Significant Figures in Measurements

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position and displacement

Tracking Motion with Position and Displacement

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position and displacement vectors

Using Vectors to Describe Motion

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mass and weight

How Mass Differs from Weight

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acceleration due to gravity on earth

Free-Fall Acceleration on Earth

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tension

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gravitational force

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Gravity is a force that pulls objects toward one another. On Earth, this force gives objects weight and keeps people, water, and other materials from drifting away. It also helps explain why planets and moons stay in motion around larger bodies. The strength of gravitational force depends on the masses of the objects involved. Larger masses create a stronger pull, while smaller masses create a weaker one. The distance between objects also matters, because gravity becomes weaker as objects move...

key terms and concepts

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

Measurement Units, Standards, and SI Basics | 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.

mechanical engineering

Measurement Units, Standards, and SI Basics

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