Welcome to UK420

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customize your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more!

This message will be removed once you have signed in.


troy

science vs religion

1,123 posts in this topic

so they do move in one direction then?

lol love it, lets see where this one leads...

In AC the electrons change direction every 1/100 of a second, so are basically wiggling backwards and forwards over a small (to us) distance.

DC is one direction.

I guess you are going to ask me which direction? :)

Well, I know what I used to believe, from battery negative, through radio to the battery positive..... and then when you recharged it, I thought it was recharged with electrons.

Share this post


Link to post

lol love it, lets see where this one leads...

In AC the electrons change direction every 1/100 of a second, so are basically wiggling backwards and forwards over a small (to us) distance.

DC is one direction.

I guess you are going to ask me which direction? :)

Well, I know what I used to believe, from battery negative, through radio to the battery positive..... and then when you recharged it, I thought it was recharged with electrons.

You have to be really careful about how you think electricity moves direction wise because there was a convention error when labelling the cathodes and anodes, before they knew they had to guess, then once they could confirm and found the electrodes were incorrectly labelled the convention was established. Electricity, or the effects of something, move in the opposite direction to the labled anode and cathode. Look up convention error, cathode anode.

Here is one description.

http://www-spof.gsfc.nasa.gov/Education/woppos.html

Edited by Hir
1 person likes this

Share this post


Link to post

Look up convention error, cathode anode.

Here is one description.

http://www-spof.gsfc.nasa.gov/Education/woppos.html

lol, yes, I am aware of it, conventional current vs electron current, and never mind the old valve days, it still happens now, all today's semiconductor circuit diagrams are drawn to the conventional current model,

Share this post


Link to post

lol, yes, I am aware of it, conventional current vs electron current, and never mind the old valve days, it still happens now, all today's semiconductor circuit diagrams are drawn to the conventional current model,

@@Rex Mundi

This bit really confuses me. The diagrams are drawn to the convention, it is important to know the direction because many electronic devices act directionally. So are we saying, science is the we there, that all batteries are wired up against convention so that a plus is really negative. Electricity must move from the plus terminal to the base/negative terminal else you can't expalin the actions of say diodes or transistors. Are batteries labelled 'wrong' ?

1 person likes this

Share this post


Link to post

The cct diagrams are drawn to the conventional current model.

Take a simple relaxation oscillator made out of a unijunction (UJT) transistor.

This one for example source: http://www.circuitdiagram.org/simple-led-flasher-using-2n2646-ujt-transistor.html

led-flasher-using-2n2646.gif

According to that circuit, the capacitor charges positive via R1 over time, till a certain positive voltage is reached, then the UJT triggers, the charge on the capacitor dissipates to ground (negative) via the led, along with current through R2, causing the LED to flash, the ujt turns off, the cycle starts again.

the waveform on the capacitor will be something like this

UJT-relaxation-oscillator-waveform.png

But as you see, conventional current pos to neg

Edited by Rex Mundi

Share this post


Link to post

So, gravity.... which is it, Newtonian force or GR curved space-time fabric which only appears to be a force?

How it can be both makes no sense to me.

But thank you, I guess you mean that I do make sense sometimes :)

eta... also, I doubt that God said "Let there be Light".... but who wants to argue about who said what...

GR superseeded Newtonian model, relegating Newtonian mechanics to 'special case' of GR (Even though Newtonian mechanics is perfectly suited to most things we see in daily life, with GR initially only accounting for small observational discrepencies in things like the orbit of Mercury, etc. (although I'm told GPS relies heavily on GR to be accurate)). Lewis Carrol would swear that reality is made of fields rather than particles. Could this be a case of trying to replace reality with descriptive mathematics though? I think this clip of Feynman being asked to describe magnetic force is quite brilliant at explaining why such a 'force at a distance' actually can't be explained at all, except to say it has to be accepted on some level to exist and that it can be crudely described but not really explained in terms of something else with which we are more familiar with (a bit like time?):-

Edited by Galactic
1 person likes this

Share this post


Link to post

Einstein's understanding of the sub atomic world was wrong.

1 person likes this

Share this post


Link to post

GR superseeded Newtonian model, relegating Newtonian mechanics to 'special case' of GR etc

But you are still not helping resolve my problem... is gravity a force or not?

According to Newton, gravity is a force

According to Einstein, it is a pseudo force, it is not a real force, it only appears to us to be a force.

According to the BBC Horizon docu i linked to earlier which I quoted here: http://www.uk420.com/boards/index.php?showtopic=262538&page=56#entry4190058

"...any object that passes through that warped spacetime, will move as if being pulled by a force and that's what we experience as gravity"....

If GR superseded Newtonian, then you seem to be saying gravity is not a force, is that so?

Edited by Rex Mundi

Share this post


Link to post

Einstein's understanding of the sub atomic world was wrong.

How comes?

Share this post


Link to post

But you are still not helping resolve my problem... is gravity a force or not?

According to Newton, gravity is a force

According to Einstein, it is a pseudo force, it is not a real force, it only appears to us to be a force.

According to the BBC Horizon docu i linked to earlier which I quoted here: http://www.uk420.com/boards/index.php?showtopic=262538&page=56#entry4190058

If GR superseded Newtonian, then you seem to be saying gravity is not a force, is that so?

They're both just descriptive models. Einsteins model gives more accurate predictions/results.

I'm not sure yet whether distinction of force / pseudo-force is neccesary. Do we have an accurate idea of what we mean by a 'proper' force?

1 person likes this

Share this post


Link to post

They're both just descriptive models. Einsteins model gives more accurate predictions/results.

I'm not sure yet whether distinction of force / pseudo-force is neccesary. Do we have an accurate idea of what we mean by a 'proper' force?

It is great to sleep on things ;)

Yes, Einsteins model was certainly more accurate, but that does not help with why we still accept that Newton was right too, that is what I find odd.

But your second point, that is what I slept on... and I'm with you there...

Is gravity the same as magnetism?

Share this post


Link to post

I can certainly feel a force when I push the similar magnet poles together... and I find it hard to separate the opposite poles, I find the only way is to slide them apart... is what I'm feeling a 'proper' force?

If it's not an unreasonable question... is gravity the same as magnetism?

Edited by Rex Mundi

Share this post


Link to post

is gravity the same as magnetism?

no, it doesn't work in the opposite way for a start, matter just attracts matter, it doesn`t repel

and you can turn off a magnet (eletro) or demagnetise, but you can`t turn off gravity

Edited by ratdog
1 person likes this

Share this post


Link to post

no, it doesn't work in the opposite way for a start, matter just attracts matter, it doesn`t repel

lol I think that I will rephrase the question...

If we accept that magnetism is a force, and what I feel pushing them together suggests tome it is... then is gravity a force too, but one that attracts only?

With unlike poles on the magnets, as they get closer I feel the force of attraction getting stronger until there is a snap distance and they snap together.

I do not feel the same increase in force with the attract-only gravity.

I have done some experiments recently that has convinced me that gravity is not a force, and what I felt during all stages of this experiment was just acceleration.

What is causing the acceleration we call gravity... Is it;

a: a Newtonian force

b: Einsteins warped 4d space-time, so just an apparent force

c: both of the above (the currently accepted model)

d: none of the above

I vote d :)

Share this post


Link to post

lol I think that I will rephrase the question...

If we accept that magnetism is a force, and what I feel pushing them together suggests tome it is... then is gravity a force too, but one that attracts only?

With unlike poles on the magnets, as they get closer I feel the force of attraction getting stronger until there is a snap distance and they snap together.

I do not feel the same increase in force with the attract-only gravity.

I have done some experiments recently that has convinced me that gravity is not a force, and what I felt during all stages of this experiment was just acceleration.

What is causing the acceleration we call gravity... Is it;

a: a Newtonian force

b: Einsteins warped 4d space-time, so just an apparent force

c: both of the above (the currently accepted model)

d: none of the above

I vote d :)

Any force, gravitational or magnetic, by definition causes accelaration though. The indistinguishability between being acted upon by a gravitational field and being in an accelarated frame of reference was Einstein's insight with regards to General Relativity.

1 person likes this

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now