Robust debate - Technical discussions.

[WotEver]

The spaces!

That'll be current then )

 

186,000 miles an hour or thereabouts.

Edited February 28, 2016 by WotEver

[Theo]

Did you know that the average drift velocity of electrons is very slow? In the life of a torch battery it is likely that an electron wil not have made one complete turn of the circuit.

 

Anyone like me to do the calculation?

 

N

[WotEver]

That's why I was relieved when Mike said 'holes'

[Theo]

That's why I was relieved when Mike said 'holes'

[cuthound]

That's why I was relieved when Mike said 'holes'

I seem to recall that the holes were created by the electrons moving on, so surely the speed of "hole flow" will be the same as electron flow?

[WotEver]

I seem to recall that the holes were created by the electrons moving on, so surely the speed of "hole flow" will be the same as electron flow?

Nope. Think of a very (very!) long hose pipe full of marbles. If you push a marble in one end then another will pop out of the other end immediately, instant 'hole'. However, because of the length of the hose it will take a long time before the marble you pushed in gets to the other end itself.

 

Tony

[BruceinSanity]

Nope. Think of a very (very!) long hose pipe full of marbles. If you push a marble in one end then another will pop out of the other end immediately, instant 'hole'. However, because of the length of the hose it will take a long time before the marble you pushed in gets to the other end itself.

Tony

'ere, I just tried that and you're quite right.

 

Now, 'ow the 'ell do I get them marbles out of my water tank, eh?

 

?

[Paul C]

The "hole" flowrate is 0. The holes don't move - they are either occupied or vacant. However, by inventing an arbitrary "free hole" parameter you can define it in a way which makes the holes appear to go very fast!

 

 

Its like me arranging beforehand, to set off from London in a red VW Passat. Then someone else, 1 minute later, arrives in Edinburgh in a similar red VW Passat. A Passat has arrived, apparently very quickly, but its not the Passat I am in.

[Loafer]

That'll be current then )

 

186,000 miles an hour or thereabouts.

 

Per SECOND, old boy. PER SECOND.

 

Come on!

[WotEver]

 

Per SECOND, old boy. PER SECOND.

 

Come on!

Oh yeah...

Its like me arranging beforehand, to set off from London in a red VW Passat. Then someone else, 1 minute later, arrives in Edinburgh in a similar red VW Passat. A Passat has arrived, apparently very quickly, but its not the Passat I am in.

Didn't Schrödinger say that it might be?

 

Or was that Occam?

 

This beer's good.

[Loafer]

Oh yeah...

 

It is MOST unlike you to get your units wrong, Wotevaaaar. Have you been kidnapped? I'm beginning to think that someone may have taken over your keyboard.

 

Send suitable message here so that we know it's YOU.

[WotEver]

Okay then... 299792458 m/s or 173 AU/d if you prefer

[Loafer]

Okay then... 299792458 m/s or 173 AU/d if you prefer

 

Hmm. I'm going to have to get Mrs Loafer involved now. She's got the calculator.

 

There's only one way THAT's going to end, so I give in! It really IS you!

[cuthound]

Nope. Think of a very (very!) long hose pipe full of marbles. If you push a marble in one end then another will pop out of the other end immediately, instant 'hole'. However, because of the length of the hose it will take a long time before the marble you pushed in gets to the other end itself.

 

Tony

Thanks Tony,

 

It's all clear to me now.

[Theo]

There is a number of analogies that are useful in explaining electrical current and voltage. I have tried the water analogy and that can work well but only if the pupils understand water flow and pressure differences. Might seem obvious to us but the children that I taught often had a deal of difficulty. For a series circuit I thought up a bicycle chain analogy. Tension in the chain is voltage. Speed of the chain around the loop is current and is the same all around. The chine wheels and pedals are the power source etc. etc.

 

N

[HappyDayz]

The "hole" flowrate is 0. The holes don't move - they are either occupied or vacant. However, by inventing an arbitrary "free hole" parameter you can define it in a way which makes the holes appear to go very fast!

 

 

Its like me arranging beforehand, to set off from London in a red VW Passat. Then someone else, 1 minute later, arrives in Edinburgh in a similar red VW Passat. A Passat has arrived, apparently very quickly, but its not the Passat I am in.

You just messed up the theory of chances having transporters like in Star Trek

 

Alan

[Mac of Cygnet]

You just messed up the theory of chances having transporters like in Star Trek

 

Alan

 

Well, I don't know. This thread has been transported from 29 Feb to now in the blink of an eye.

[Phil Ambrose]

Zombies get everywhere.

Phil

[metanoia]

Zombies get everywhere.

Phil

In their own time and space, Flappy!!

 

M x

 

ETA - and STILL can't find Wot Ever at Springwood Haven - he's even disappeared from the outside moorings at Trinity now - must be a very big black hole on the Cut in these parts ..... Beam me back Ooop North, please!

Edited September 10, 2016 by metanoia

[Phil Ambrose]

In their own time and space, Flappy!!

 

M x

 

ETA - and STILL can't find Wot Ever at Springwood Haven - he's even disappeared from the outside moorings at Trinity now - must be a very big black hole on the Cut in these parts ..... Beam me back Ooop North, please!

Working on it as we speak.

Phil

[WotEver]

I sold the boat about 3 years ago. Last seen looking uncared for and sorry for herself on the linear moorings at Trinity on the Ashby.

[FORTUNATA]

I guess I am occasionally guilty of going off in a new direction. I can see the point Dan is driving at. Some poor so-and-so has a blown alternator diode and ends up with a discussion on the Theory Of Relativity. Having said that, all education is good. No harm in exercising the cerebral muscles. As I recall there did used to be some pretty ferocious electrical debates on the site. Almost along the lines of Blood Sports. That has now calmed a lot and few signs of heated exchange.

[Sea Dog]

Hmm, maybe "Advice re car radio" is one such current thread? When the OP eventually returns with an Electronics Degree he's gonna be awfully disappointed!

[FORTUNATA]

Electronics is a really "bitchy" field. I was banned from two vintage radio sites simply because somehow I didn't follow the social pecking order rules. The impression I got was the members were somehow carrying a chip on their shoulder over the collapse of the TV repair industry. There was one individual who seemed to spend his time waiting for me to make some mistake. I did do once with a simple maths calculation on Ohms Law. Then he pounced and created a drama. Also used the sarcastic put-down in the style of, "Ohms Law is a good thing for you to learn you know!" To be honest, in books I've encountered simple maths mistakes by very high-ranked experts but they were just of the absent minded variety. Most common is when the source voltage is said to be 260 AC but the figures are then based on 230. I am hardly going to be stupid enough as to declare the individual doesn't know Ohms Law. What really amazed me once was a review on Amazon that referred to Rick Mcwhorter's electronics repair book. There was an undergraduate student who slammed the book and called the author "a tinkerer who doesn't understand electrical theory". This was due to some silly misprints such as "sign wave" and undetected maths blunders. Yet, in actual fact, Mcwhorter is incredibly good in his field. I discovered he was trained in the Air Force and worked on jet engines. He was slammed by critics for using the term "positive bias" when strictly he should have said "less negative" but to me it was clear what he meant. Surely it's not wrong to call 2 volts negative "positive" compared to 4 volts negative? Yet he was savaged by critics.

[Guest]

Electronics is a really "bitchy" field. I was banned from two vintage radio sites simply because somehow I didn't follow the social pecking order rules. The impression I got was the members were somehow carrying a chip on their shoulder over the collapse of the TV repair industry. There was one individual who seemed to spend his time waiting for me to make some mistake. I did do once with a simple maths calculation on Ohms Law. Then he pounced and created a drama. Also used the sarcastic put-down in the style of, "Ohms Law is a good thing for you to learn you know!" To be honest, in books I've encountered simple maths mistakes by very high-ranked experts but they were just of the absent minded variety. Most common is when the source voltage is said to be 260 AC but the figures are then based on 230. I am hardly going to be stupid enough as to declare the individual doesn't know Ohms Law. What really amazed me once was a review on Amazon that referred to Rick Mcwhorter's electronics repair book. There was an undergraduate student who slammed the book and called the author "a tinkerer who doesn't understand electrical theory". This was due to some silly misprints such as "sign wave" and undetected maths blunders. Yet, in actual fact, Mcwhorter is incredibly good in his field. I discovered he was trained in the Air Force and worked on jet engines. He was slammed by critics for using the term "positive bias" when strictly he should have said "less negative" but to me it was clear what he meant. Surely it's not wrong to call 2 volts negative "positive" compared to 4 volts negative? Yet he was savaged by critics.

Sounds like some members on here!