Name: si units and metric prefixes
Uploaded: 2023-09-22T11:49:19.000Z
Duration: 1 min 29 s
Channel: JoVE

K12 Standards

Texas Essential Knowledge and Skills

High School

Specialised Topic in Science

112.51.c.1.

112.51.c.1.E.

International System of Units

The international system of units is widely accepted across the world, and the base units are meters, kilograms, and seconds. These units are absolute, and their value does not alter based on location.
Prefixes are used to define larger and smaller quantities. Milli, micro, and nano are used to denote smaller quantities, while kilo, mega, and giga are used to denote larger quantities.
However, among the base units, the kilogram is the only base unit defined with a prefix.
A few rules need to be followed while expressing units and prefixes. Firstly, dots are used to differentiate units in composite units.
Secondly, a prefix is avoided in the denominator and is only expressed in the numerator of the composite unit.
Thirdly, the exponential power on a unit with a prefix applies to the prefix and its unit, and finally, the result is represented using a single prefix.
Unlike the metric system, the SI does not use multiples of deca or centi.

international system of units

The International System of Units, known as the SI system, is a universally accepted measurement system recognized and used worldwide. The SI system is based on a set of three base units considered absolute, and their values do not change with location. These base units are meters, kilograms, and seconds.
Prefixes are used to define both larger and smaller quantities in the SI system. For example, milli, micro, and nano define smaller quantities, while kilo, mega, and giga are used to define larger quantities. The kilogram is the only base unit defined with a prefix among the SI system&#39;s base units.
Several rules must be followed while expressing units and prefixes. Firstly, dots are used to differentiate units into composite units. Secondly, a prefix is avoided in the denominator and is only expressed in the numerator of a composite unit. Thirdly, an exponential power on a unit with a prefix applies to the prefix and its unit. Finally, results are represented using a single prefix.
It is essential to note that, unlike the metric system, the SI system does not use multiples of deca or centi. The SI system&#39;s prefixes are based on powers of ten, with the base unit having no prefix. SI units are intended to simplify and standardize scientific measurements by leveraging a universal system.
One of the primary reasons the SI system is used worldwide is its accuracy and precision in measurement. Even the most minuscule and massive quantities can be quantified accurately with their base units and prefixes.
The SI system&#39;s base unit of length is the meter, defined as the distance light travels in a vacuum during a specific time frame. Other measurements, such as a centimeter, a kilometer, and a millimeter, can be derived from the meter using the prefix system.
The SI system&#39;s base unit of mass is the kilogram, defined as the amount of mass of a set of foundational objects known as the International Prototype of the Kilogram. Other mass measurements, such as grams and milligrams, can be derived from the kilogram using the prefix system.
The SI system&#39;s base unit of time is the second, defined as the duration of 9,192,631,770 cycles of the radiation associated with a specific transition between energy levels of a cesium-133 atom. From the second, other time measurements, such as a minute and an hour, can be derived using the prefix system.
In addition to these units, four more are defined as the fundamental units of measurement. They are the ampere, Kelvin, mole, and candela.

The International System of Units, known as the SI system, is a universally accepted measurement system recognized and used worldwide. The SI system is ...

Education

JoVE Core

Mechanical Engineering

Unit 1

An Introduction to Statics

KEY TERMS AND CONCEPTS

si units and metric prefixes

SI units and metric prefixes provide a standard way to measure size, mass, and time. The International System of Units, or SI system, is used worldwide because it gives scientists a common language for measurement. Its values do not change with location, which helps keep results consistent.

The SI system is built on three base units: meter, kilogram, and second. These are the core units for length, mass, and time. The kilogram is the only base unit that already includes a prefix.

Prefixes make it easy to express very large or very small values. Milli, micro, and nano represent smaller quantities. Kilo, mega, and giga represent larger quantities. SI prefixes are based on powers of ten, and the base unit has no prefix.

Several rules apply when writing SI units. Dots are used to separate units in composite units. A prefix should not appear in the denominator, only in the numerator. If a unit with a prefix is raised to a power, the power applies to both the prefix and the unit. The final answer should use just one prefix. Unlike the metric system, SI does not use deca or centi.

SI units help simplify and standardize scientific measurements. They also improve accuracy and precision, even for very small or very large quantities. The meter is defined as the distance light travels in a vacuum during a specific time frame. Other length units, such as centimeter, kilometer, and millimeter, come from the meter.

The kilogram is the SI base unit of mass. It was defined as the mass of a set of foundational objects called the International Prototype of the Kilogram. Grams and milligrams are derived from the kilogram. The second is the SI base unit of time and is defined by 9,192,631,770 cycles of radiation from a specific transition in cesium-133. Minutes and hours can be derived from the second. Four more fundamental units are also part of SI: ampere, Kelvin, mole, and candela.

SI Units and Metric Prefixes

an introduction to mechanics

Mechanics in Physics and Engineering

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basic concept

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units of measurement

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...

SI units and metric prefixes provide a standard way to measure size, mass, and time. The International System of Units, or SI system, is used worldwide because it gives scientists a common language for measurement. Its values do not change with location, which helps keep results consistent. The SI system is built on three base units: meter, kilogram, and second. These are the core units for length, mass, and time. The kilogram is the only base unit that already includes a prefix. Prefixes...

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accuracy, limits, and approximation

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key terms and concepts

Learn how SI units use meters, kilograms, seconds, and metric prefixes to measure length, mass, and time with accuracy and consistency.

SI Units and Metric Prefixes | 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

Physics

PHYS.1

PHYS.1.E

Chemistry and Physics

IPC.1

IPC.1.E

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Inductive Reasoning

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Deductive Reasoning

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Correlation and Causation

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Ask questions and define problems related to specialized topics of study based on observations or information from text, phenomena, models, or investigations;

112.51.c.1.A.

Scientific Method

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Apply science practices related to specialized topics of study to plan and conduct investigations or use engineering practices to design solutions to problems;

112.51.c.1.B.

Proper Personal Protective Equipment

Robert M. Rioux &#38; William A Elliott, Pennsylvania State University, University Park, PA
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Emergency Eyewash and Shower Stations

Robert M. Rioux, Pennsylvania State University, University Park, PA
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Working with Centrifuges

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Robert M. Rioux &amp; Zhifeng Chen, Pennsylvania State University, University Park, PA
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Fume Hoods and Laminar Flow Cabinets

Robert M. Rioux &amp; William A. Elliott, Pennsylvania State University, University Park, PA
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Users are responsible for the proper disposal of the waste ...

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112.51.c.1.C.

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112.51.c.1.D.

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112.51.c.1.F.

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112.51.c.1.G.

Scientific Laws and Theories

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112.51.c.1.H.

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112.51.c.2.A.

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112.51.c.2.B.

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112.51.c.2.C.

Scientific and engineering practices. The student, for at least 40% of instructional time, asks questions, identifies problems, and plans and safely conducts classroom, laboratory, and field investigations to explain phenomena or design solutions using appropriate tools and models. The student is expected to:

SI Units and Metric Prefixes

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