26 oktober, 2011

Uppdaterat SI-system

Via @KarinBojs såg jag att The General Conference on Weights and Measures har enhälligt röstat för att inleda processen med att byta definitionerna av enheterna kilogram, Ampere, mol och Kelvin.

Bild från New Scientist.
I stället för att kilot skall definieras av en metallklump i Paris skall man sätta ett konstant värde på Placks konstant. Även elektronens laddning, Bolzmanns konstant och Avogadros tal kommer att få bestämda värden på samma sätt som ljusets hastighet i vacuum idag är definierad som exakt 299792458 meter per sekund.

Jag har skrivit tidigare här på bloggen om arbetet med att byta SI-definitionerna. Det är framförallt kilo och Ampere som ställt till problem med sina konstiga definitioner; kilot som massan av en klump metall och Ampere som en ström genom oändligt långa ledare i vakuum. Det sistnämnda kan vara något svårt att reproducera i ett labb. Den konstiga definitionen på  Ampere har gjort att man för länge sedan använder alternativa definitioner i praktiska tillämpningar och det man nu mäter egentligen är en enhet oberoende av SI-enheten (även of den har samma värde).

6 kommentarer:

emilyfong sa...

Det sistnämnda kan vara något svårt att reproducera i ett labb?

Unknown sa...

Jag lyckades få en kredit mellan privata sir. Diego Zumerle, förhållandena är bra såväl som återbetalningsläget. Det är verkligen allvarligt att räntan är 3%. Om du också behöver en kredit på 5000 kr upp till 12.000.000 kr, här är hans e-postadress: diegozumerle71@gmail.com

manoj sa...

We offer personal Business loans services around the world. We strive to provide high
quality service and high customer satisfaction, while possible financial services.
We pride ourselves on our commitment to our customers;
We can give you personal loans, auto loans, business / investment loans,
short term loans. You can contact us for an affordable loan now at 2% interest rate.
Contact us now via E-mail: (excelsiorfunds@seznam.cz)
whatspp Number +447448521995

Unknown sa...

Dear Customers,

We invite you all to participate in our new business and project funding program, We are currently funding for Business start-up Business developments, Business acquisition Business expansion, Project funding, and Working capital, etc.

This Funding program allows a client to enjoy a 3% low-interest rate and payback period of 1 to 35 years. We can approve a loan/funding for up to $500,000,000.00 or more depending on the nature of the business we are currently funding for and we satisfy our customers’ financial needs and help them succeed

Application Available
Apply via E-mail: standardonlineinvestment@gmail.com
Regards,
Mr. Hameed Youssef
Marketing Manager
Standard Online Finance Ltd.

manoj sa...


Express Loan Offer
Do you need financial aid, are you seriously in need of an urgent loan, to start up your own business, you're in debt and no funds for payment ? This is your chance to reach your desire goals because we give out personal loan, business loans, and all kinds of loan at 2% interest rate.... information contact us via Email:
(excelsiorfunds@seznam.cz)
whatspp Number +447440711562

Borrower's INFORMATION:
Full Name: _______
Loan amount needed: _____
Loan Duration: _____
Occupation_____
Purpose: _____
Phone: ____
Country: ____

Dr, Benjamin Owen sa...

AFFORDABLE/COMFORTABLE LOAN OFFER WITHOUT COST/STRESS CONTACT US VIA Call/Text +1(646)820-1981 WhatsApp: +19292227023 Email drbenjaminfinance@gmail.com
Loan Company Website: https://capitalmanage-inc.com/

Do you find yourself in a bit of trouble with unpaid bills and don’t know which way to go or where to turn? What about finding a reputable Debt Consolidation firm that can assist you in reducing monthly installment so that you will have affordable repayment options as well as room to breathe when it comes to the end of the month and bills need to get paid? ®Capital Managements Inc™ is the solution to your financial misfortune. We offer all types of loan ranging from $5,000.00 to $533,000,000.00USD with a low interest rate of 2% and loan duration of 1 to 35 years to pay back the loan secure and unsecured. Our loans are well insured for maximum security is our priority, Our leading goal is to help you get the services you deserve, Our program is the quickest way to get what you need in a snap. Kindly reduce your payments to ease the strain on your monthly expenses by Contacting us on the following WhatsApp:+19292227023 Email drbenjaminfinance@gmail.com

Loan Offer Alert For Everyone! Are you financially down and you need an urgent credit/financial assistance? Or are you in need of a loan to start-up/increase your business or buy your dream house. GET YOUR INSTANT LOAN APPROVAL 100% GUARANTEED TODAY NO MATTER YOUR CREDIT SCORE. drbenjaminfinance@gmail.com
Capital Managements Inc Website: https://capitalmanage-inc.com/