electrostats

Equation #10: Gauss’ Law

Every charge produces an electric field around it. Coulomb’s law comes in handy when we have one or two charges. It gets really cumbersome to use Coulomb’s law for calculations involving a bunch of charges and quite impossible when we have a macroscopic charged object, like a rod or sphere etc. 

Gauss’ law helps you out in such cases, provided you have some kind of symmetry in the charge distribution. Most commonly we deal with planar, cylindrical and spherical symmetries. If you have a charged symmetric object, you just have to imagine a surface enclosing it and depending on the charge enclosed (calculated by charge density per unit length, area or volume), you can calculate the electric flux. 

The electric flux is a quantity which is somewhat abstract. Basically, it gives you the “net amount of electric field lines” exiting that imaginary surface. For example, if you don’t have any charge enclosed, the amount of electric field lines going in = the amount of field lines coming out, hence net flux is zero. 

An interesting song that will help you remember Gauss’ Law:

https://www.youtube.com/watch?v=RnPy0jJYZX0

More details: 

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/gaulaw.html
http://www.maxwells-equations.com/gauss/law.php

https://www.youtube.com/watch?v=Zu2gomaDqnM

electrostatic potential (7/?)

ten/rose. teen this ch.
i’m a little late today, but it’s still wednesday by my clock! you guys may really start scratching your heads after this one… or maybe it’ll be the one that gives you the revelation you’ve been waiting for! it’s hard for me to say. hope you enjoy either way :) thanks to @shutupandlovetennant​ and @goingtothetardis​ as usual!
summary: as the doctor and rose traverse time and space looking for adventure, they slowly fall victim to a mysterious energy that can manipulate their emotions. though confused and unnerved by the cerebral affliction, neither of them understands its cause, or realizes that it could jeopardize their friendship. what will it take for them to discover the truth?
this chapter on ao3 | back to chapter 1 on ao3

The Doctor is acting weird.

He was jumpier than ever over dinner last night. And he never explained what on Earth had startled him enough to make him flee the kitchen with his tea spilled all over the floor, his favorite mug broken amidst the tiny lakes of blue. He’d been watching her all evening, wide eyes and restless limbs, like he was waiting for her to morph into a zombie. Eat his brains. Or something he would find comparably horrifying.

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Martin Logan Renaissance ESL 15A Install!

Hi All,

I don’t normally do a blog regarding an install I have just done but this was rather special so I couldn’t help myself on this occasion, basically one of our customers has been a Martin Logan user for many years and it was time for an upgrade and he was particularly interested in the new Martin Logan Renaissance Electrostatic speakers with active room correction so a home demo was organised.

Firstly these are rather on the large side, I was particularly surprised by the size of the bass unit, it is huge and they weigh a tonne but once in place we started with the room correction, this is extremely easy to setup, basically all you need is a laptop and the Martin Logan Perfect Bass Kit which comprises of some software and a microphone and off you go, it takes a basic reading of your room then takes several readings of each speaker, you then click optimise and all the clever stuff happens and then you upload to the Renaissance speakers and that is it, and the difference is extremely noticeable as with any hybrid design like this the toughest part is getting the panel to integrate with the dynamic bass drivers, Martin Logan have made massive strides in this area over the years so you really do not notice the crossover from the panel to bass and this really helps once again with the integration, really cleaning and tightening the bottom end up, very impressive as you can turn the eq off and compare but it doesn’t take long before you realise that the eq needs to stay on :-)

Once done it was a matter of listening and I can say I have never heard anything quite like it, I love the Logan sound, very transparent, great separation and clarity but it was the size of the image that was so impressive thanks to the huge 15″ wide panels, to get an idea of size the Pioneer TV below is a 60″ and it is dwarfed by the Logan’s, just epic :-)

http://hifilounge.co.uk/martin-logan-renaissance

I am just waiting for the new model below the Renaissance to come in for demo which shouldn’t be too much longer so if you would like to hear the difference the room correction makes please feel free to get in touch.

Below are a couple of pictures of the Renaissance at the customers, needless to say after trying them at home he ordered a pair.

Cheers,

Paul.

electrostatic potential (6/?)

ten/rose. pretty adult this ch.
hey guys, I’m back! recovering from surgery really well. this is a rather short chapter, but it is something of a turning point! hope you guys enjoy, and that you don’t go too crazy with curiosity :) thank you @shutupandlovetennant​ and @goingtothetardis​ as usual!
summary: as the doctor and rose traverse time and space looking for adventure, they slowly fall victim to a mysterious energy that can manipulate their emotions. though confused and unnerved by the cerebral affliction, neither of them understands its cause, or realizes that it could jeopardize their friendship. what will it take for them to discover the truth?
this chapter on ao3 | back to chapter 1 on ao3

The Doctor has found himself in quite the quandary. Ordinarily (occasional hiccups that the TARDIS won’t help him resolve aside), repressing memories and directing his mind away from unproductive thoughts is his specialty. Time Lords possess exceptional control over their conscious minds, and honing these skills even further was his only coping mechanism in the aftermath of the Time War.

Who would have thought that one kiss could render his superior neurobiology and years of training useless?

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