Soldato
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I'm mechanical too, I like to know a bit about all sorts though so I latch onto the odd 'trician if I'm doing noting at work.
Batteries in series: how does this work?
- Thread starter Devrij
- Start date
I'm mechanical too, I like to know a bit about all sorts though so I latch onto the odd 'trician if I'm doing noting at work.
Soldato
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- 18 Oct 2012
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Always handy, saves using dc and rheostats for everything when you know a bit about the proper way of doing it, some ac devices like induction motors or rccb's boggle the mind with their elegant simplicity
Oh Damn, I am going to have to remember loads of stuff
(It is actually decades since I last had to deal with this seriously)
The tricky bit is trying to explain it to people who are smart but have not necessarily done the course.
What I don't get though is if you short circuit a battery we all know what happens, but why does it not happen when you connect the positive and negative ends of separate batteries? The way I understand batteries you have a positive and negatively charged side separated by a dielectric. That potential difference in charge is what creates current when you create a circuit. So why is there no potential difference between the positively charged end of one battery and the negatively charged side of a different battery?
Soldato
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2 sources with no load = no flow of current
Because there isn't a closed circuit so there is no flow. By connecting two batteries in series you will double the voltage, so two 1.5v batteries would produce 3v.
Soldato
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Bigger amps = Death.
Bigger voltage = Static electricity.
+ will always choose the fastest root to - either though you or anything in between.
Just don't mess with amps they the killer.
Yep - Electric fences can have over 10,000V running through them.
But very little amperage.
Still stings like a mofo tho!
Because placing them top to tail there's no circuit, and no charge will move!
If you did that and then placed a wire between the ends that would be a short circuit.
Just matching the + and - of something doesn't make a circuit - they're just to label the ends so you get the polarities right.
When you touch the + of one to the - of the other the contact means that those points are at the same potential.
Let's try some pictures with voltage labels:
One 1.6 V cell: 0V |---|+ 1.6V
Two in series: 0V |---|+ |---|+ 3.2V
With labels in the middle: 0V |---|+ 1.6V 1.6V |---|+ 3.2V
Or let's call the 1.6V point our zero: -1.6V |---|+ 0V 0V |---|+ 1.6V
(We can do that because they're all just relative differences.)
Soldato
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But you haven't created a circuit by touching two batteries end to end. Plus we a dealing with potential differences, note the word potential, which only becomes an actual once you complete a full circular loop.
{3v====0v] is a simplified battery with a potential difference of 3v.
Put two together, you get
{6v====3v]{3v====0v]
If you were to then put a wire between the +ve terminal of the left battery and the -ve terminal of the right one, that is a short circuit, because it is an actual circuit, with no load.
Edit: Bah ginger stepchild.
Right.
Capacitance=Water flowing into a tank. As it fill the "Pressure" at the outflow (at the bottom) builds up. Once the tank is full the filling tap can be switched off and the water can be allowed to flow out of the tank to do work. If the tap is only opened slightly only a small amount of water will flow out and the tank will empty slowly. If the tap is opened fully the water will flow out quickly doing a lot of work in a very short time.
(Super capacitors can store a large amount of energy and release it verv quickly, say to power a z-pinch machine or rail gun!
)Inductance= water flowing in a large bore pipe, if the water is flowing fast then there is a considerable amount of momentum involved. If one suddenly shuts a valve, trying to instantly stop the water from flowing cab generate very high pressures (Some claim high enough to generate nuclear fusion effects!
)This is, for example, how car ignition coils work.
Now I am going to try to create an analogy of an ac circuit. This might take some time
Right.
Capacitance=Water flowing into a tank. As it fill the "Pressure" at the outflow (at the bottom) builds up. Once the tank is full the filling tap can be switched off and the water can be allowed to flow out of the tank to do work. If the tap is only opened slightly only a small amount of water will flow out and the tank will empty slowly. If the tap is opened fully the water will flow out quickly doing a lot of work in a very short time.
(Super capacitors can store a large amount of energy and release it verv quickly, say to power a z-pinch machine or rail gun!
Inductance= water flowing in a large bore pipe, if the water is flowing fast then there is a considerable amount of momentum involved. If one suddenly shuts a valve, trying to instantly stop the water from flowing cab generate very high pressures (Some claim high enough to generate nuclear fusion effects!
This is, for example, how car ignition coils work.
Now I am going to try to create an analogy of an ac circuit. This might take some time
Easy, it's like when you try to get the air out of a beer bong. You raise one end and then you raise the other. The beer flows each way depending on which end is raised. Here, mavity is representing the change in voltage direction. Is that right?
Soldato
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Right.
Capacitance=Water flowing into a tank. As it fill the "Pressure" at the outflow (at the bottom) builds up. Once the tank is full the filling tap can be switched off and the water can be allowed to flow out of the tank to do work. If the tap is only opened slightly only a small amount of water will flow out and the tank will empty slowly. If the tap is opened fully the water will flow out quickly doing a lot of work in a very short time.
(Super capacitors can store a large amount of energy and release it verv quickly, say to power a z-pinch machine or rail gun!
Inductance= water flowing in a large bore pipe, if the water is flowing fast then there is a considerable amount of momentum involved. If one suddenly shuts a valve, trying to instantly stop the water from flowing cab generate very high pressures (Some claim high enough to generate nuclear fusion effects!
This is, for example, how car ignition coils work.
Now I am going to try to create an analogy of an ac circuit. This might take some time
well played, google 'hydram' it's the mechanical equivalent of a magneto used for pumping water up to high places.
ac single phase can be better thought of like an oscillating linkage [like a piston in an engine] but i've yet to figure out a good one for 3 phase.