User talk:Williamborg/sandbox4

Jørgen Brekke
Born	(1968-04-26) 26 April 1968 Oslo, Norway
Occupation	Crime Novelist
Nationality	Norwegian
Genre	Crime fiction, mystery fiction
Subject	Crime, thriller, mystery
Notable works	Where Monsters Dwell

Jørgen Brekke, born 26 April 1968 in Horten municipality, Vestfold county, Norway is a Norwegian author and journalist. He was raised in Horten, and later moved to Trondheim.

Breeke was educated as a teacher at the Norwegian University of Science and Technology in Trondheim and has worked as a journalist and personal assistant. He lives there with his wife and three children.

In 2011 he debuted with a criminal fiction novel, Nådens omkrets (published in the United States as "Where Monsters Dwell"), which has been translated into and sold in eight languages in thirty countries. It achieved substantial recognition in Norway, receiving two debut novel awards (the Norlis debutantpris and the Maurits Hansen-prisen - Nytt Blod).<ref>Vinneren av Norli debutantpris (article in Norwegian)

Bibliography

Nådens omkrets – Crime fiction (2011) Drømmeløs – Crime fiction (2012) Menneskets natur – Crime fiction (2013) Doktor Fredrikis kabinett – Crime fiction (2014)

References

{{Persondata <!-- Metadata: see [[Wikipedia:Persondata]]. --> | NAME = Brekke, Jørgen | ALTERNATIVE NAMES = | SHORT DESCRIPTION = Norwegian writer | DATE OF BIRTH = 26 April 1968 | PLACE OF BIRTH = Horten | DATE OF DEATH = | PLACE OF DEATH = }}

Category:1968 births Category:Living people Category:Norwegian writers Category:Norwegian crime fiction writers

Electrostatics

__Electrostatics: General

___Force - Coulomb's Law

$F={\frac {1}{4\pi \varepsilon _{0}}}{\frac {q_{1}q_{2}}{r^{2}}}$

${\begin{aligned}{\frac {1}{4\pi \varepsilon _{0}}}=8.987\times 10^{9}\ \mathrm {N\cdot m^{2}/C^{2}} \end{aligned}}$

ε₀ ≈ 8.85418782×10⁻¹² F·m⁻¹

____Coulomb's law: Vector

$\mathbf {F} ={1 \over 4\pi \varepsilon _{0}}{q_{1}q_{2}(\mathbf {r} _{1}-\mathbf {r} _{2}) \over |\mathbf {r} _{1}-\mathbf {r} _{2}|^{3}}={1 \over 4\pi \varepsilon _{0}}{q_{1}q_{2} \over r^{2}}\mathbf {\hat {r}} _{21},$

____Coulomb's law: System of discrete charges

$\mathbf {F} (\mathbf {r} )={q \over 4\pi \varepsilon _{0}}\sum _{i=1}^{N}{q_{i}(\mathbf {r} -\mathbf {r} _{i}) \over |\mathbf {r} -\mathbf {r} _{i}|^{3}}={q \over 4\pi \varepsilon _{0}}\sum _{i=1}^{N}{q_{i} \over R_{i}^{2}}\mathbf {\hat {R}} _{i},$

Electric Field

____Definition: Electric Field

$\mathbf {E} ={\frac {\mathbf {F} }{q}}$

____Electric field: point charge

$\mathbf {E} ={1 \over 4\pi \varepsilon _{0}}{\frac {q}{r^{2}}}.$

____Electric field: multiple point charges

$\mathbf {E} =\sum _{i=1}^{N}{1 \over 4\pi \varepsilon _{0}}{\frac {q}{r^{2}}}.$

Electric Displacement Field

The permittivity ε of a linear material, which usually differ from the permittivity of free space ε₀, is used to calculate the electric displacement field:

$\mathbf {D} =\varepsilon \mathbf {E} .$

____Relative permittivity

Materials generally have a higher permitivity ($\varepsilon$) than the permitivity in a vacuum ($\varepsilon _{0}$). Hence it is useful to define the relative permitivity ($\varepsilon _{r}$) as

$\varepsilon _{r}={\frac {\varepsilon }{\varepsilon _{0}}},$

Example values are listed below

Relative static permittivities of some materials at room temperature under 1 kHz

Material	εr
Vacuum	1 (by definition)
Air	1.00058986 ± 0.00000050 (at STP, for 0.9 MHz),
PTFE/Teflon	2.1
Polyethylene	2.25
Polyimide	3.4
Polypropylene	2.2–2.36
Paper	3.85
Electroactive polymers	2–12
Silicon dioxide	3.9
Pyrex (Glass)	3.7–10
Graphite	10–15
Silicon	11.68
Water	88 - 34.5