- published: 07 Sep 2014
- views: 94445
The International System of Units (French: Système international d'unités, SI) is the modern form of the metric system, and is the most widely used system of measurement. It comprises a coherent system of units of measurement built on seven base units. It defines twenty-two named units, and includes many more unnamed coherent derived units. The system also establishes a set of twenty prefixes to the unit names and unit symbols that may be used when specifying multiples and fractions of the units.
The system was published in 1960 as the result of an initiative that started in 1948. It is based on the metre-kilogram-second system of units (MKS) rather than any variant of the centimetre-gram-second system (CGS). SI is intended to be an evolving system, so prefixes and units are created and unit definitions are modified through international agreement as the technology of measurement progresses and the precision of measurements improves. The 24th and 25th General Conferences on Weights and Measures (CGPM) in 2011 and 2014, for example, discussed a proposal to change the definition of the kilogram, linking it to an invariant of nature rather than to the mass of a material artefact, thereby ensuring long-term stability.
The International System of Units (SI) defines seven units of measure as a basic set from which all other SI units are derived. The SI base units and their physical quantities are:
The SI base quantities form a set of mutually independent dimensions as required by dimensional analysis commonly employed in science and technology. However, in a given realization in these units they may well be interdependent, i.e. defined in terms of each other.
The names and symbols of SI base units are written in lowercase (e.g. metre (US English: meter) has the symbol m), except the symbols of those named after persons which are written with an initial capital letter (i.e., the kelvin after Lord Kelvin has the symbol K and the ampere after André-Marie Ampère has the symbol A).
Many other units, such as the litre (US English: liter), are formally not part of the SI, but are accepted for use with SI.
Crash Course (also known as Driving Academy) is a 1988 made for television teen film directed by Oz Scott.
Crash Course centers on a group of high schoolers in a driver’s education class; many for the second or third time. The recently divorced teacher, super-passive Larry Pearl, is on thin ice with the football fanatic principal, Principal Paulson, who is being pressured by the district superintendent to raise driver’s education completion rates or lose his coveted football program. With this in mind, Principal Paulson and his assistant, with a secret desire for his job, Abner Frasier, hire an outside driver’s education instructor with a very tough reputation, Edna Savage, aka E.W. Savage, who quickly takes control of the class.
The plot focuses mostly on the students and their interactions with their teachers and each other. In the beginning, Rico is the loner with just a few friends, Chadley is the bookish nerd with few friends who longs to be cool and also longs to be a part of Vanessa’s life who is the young, friendly and attractive girl who had to fake her mother’s signature on her driver’s education permission slip. Kichi is the hip-hop Asian kid who often raps what he has to say and constantly flirts with Maria, the rich foreign girl who thinks that the right-of-way on the roadways always goes to (insert awesomely fake foreign Latino accent) “my father’s limo”. Finally you have stereotypical football meathead J.J., who needs to pass his English exam to keep his eligibility and constantly asks out and gets rejected by Alice, the tomboy whose father owns “Santini & Son” Concrete Company. Alice is portrayed as being the “son” her father wanted.
This video describes the metric system, SI units, and metric conversions using conversion factors. ***Learning Targets related to this video*** Identify the metric and SI units used in science and convert between common metric prefixes. Perform calculations involving scientific notation, significant figures and conversion factors.
This is the first of eight videos exploring S.I. units. In this episode the history of the development of the seven units - the metre, kilogram, second, Ampere, Kelvin, mole and the candela is examined. This video is an excellent starting point for anyone wishing to study physics at an advanced level.
A unit is the frequently arbitrary designation we have given to something to convey a definite magnitude of a physical quantity and every quantity can be expressed in terms of the seven base units that are contained in the international system of units. Hank thinks this is a thrilling subject, and while you may not agree, it is a subject that is very important if you want to be a scientist and communicate with accuracy and precision with other scientists. So listen up and learn something or Hank might have to kill you! (NOT REALLY!) Like Crash Course? http://www.facebook.com/YouTubeCrashCourse Follow Crash Course! http://www.twitter.com/TheCrashCourse Follow ThoughtCafe! http://www.twitter.com/ThoughtBubbler Tumbl Crash Course. http://thecrashcourse.tumblr.com Table of Contents Unit Con...
From the ProEdify TEAS V prep course, this is part 1 of the lesson on units of measure. In this introduction to scientific measurements and the SI system, we discuss the scientific definition of a measurement, important SI units of measure and we break down the difference between base and derived quantities. -- Table of Contents: What is a unit of measure? - 1:12 Important base properties for TEAS V - 1:50 Base quantities vs Derived Quantities - 2:17 Explanation of unit names in SI system - 3:29 Sources Used in this Video 1) Physics 9th Edition Cutnell, John D., and Kenneth W. Johnson. "1.2." Physics. Hoboken: John Wiley & Sons, 2012. N. pag. Print. Media Attributions 1) Hexaaquatitanium(III)-solution.jpg By Benjah-bmm27 (Own work) [Public domain], via Wikimedia Commons 2) Sph...
An explanation of S.I. base units and derived units By Cowen Physics (www.cowenphysics.com)
Before the adoption of the International System of Units ( SI) , there are many different units. Today, the SI units are the adopted system of units in the scientific community because all SI units are based on seven fundamental units, prefixes, and the power of 10. I will explain this in the later video because we will focus on the different SI base units and units that are derived from the SI base units in this video. Again, all SI units are based on the seven fundamental SI units called SI base units. Currently, Liter is considered as one of the SI base units, so there are eight SI base units. The SI base units are like the 26 letters of the English alphabet. We combine the letters to make different words that have different meanings. Unlike the English alphabet, the SI units are base...
Mr. Causey teaches scientific units of the SI system, the metric system and the CGS system. Mr. Causey also shares the major prefixes and their meaning. http://yourchemcoach.com Share this Video: http://www.youtube.com/watch?v=WuaxXcgX6Rc Learn more and understand better with Mr. Causey's tutorials. Subscribe for more chemistry videos: http://bit.ly/1jeutVl Related Videos: Conversions: http://www.youtube.com/watch?v=H0vFB129gd4 Accuracy and Precision: https://www.youtube.com/watch?v=hnU7hoxPEs8 Significant Figures: https://www.youtube.com/watch?v=eM17E5YeVUw Contact Me: mrcausey@mrcausey.com Follow Me: http://www.twitter.com/#!/mrcausey http://pinterest.com/mistercausey/ http://www.facebook.com/profile.php?id=814523544 https://plus.google.com/u/0/111105504415887392612 Science mea...
This video defines the SI base unit of time, the second. Be sure to subscribe and leave any questions or suggestions in the comments below. Thanks for watching.
This is the 2nd. of eight videos exploring S.I. units. In this episode we examine the origins of the metre and look at its multiples and subdivisions to measure the very large and the very small.
Jonathan Williams discusses the seven base SI units and how they are linked. For more information: http://www.npl.co.uk/reference/measurement-units/si-base-units/
You've stolen my heart
And I want you to remember
Now what'll I do living alone?
You've stolen my heart
And it hurts me to remember
'Cause now where'll I go to living alone?
And a butterfly in the wind is drifting like I do
It's dumb, I know what I want to say
But I can't even take one breath
As night falls
I hear voices on the radio
I'll follow their dreams and wake up alone
And a butterfly in the wind is drifting like I do
It's dumb, I know what I want to say
But I can't even take one breath
So now still burning silently away