Examining DC Signals & Batteries: What's the Difference?

In summary, the problem is that the switching frequency of a battery can be very high and it is difficult to see the transitions due to the fast rate of the atomic level reactions.
  • #1
y33t
107
0
If you study a DC signal under an appropriate scope, you can see the switching transitions ; a pwm signal.

But if you examine a battery, no matter how high temporal resolution you reach, you see a dc signal.

What might be the explanation for this? electrons are being generated by a chemical process in battery and these reactions are very fast so the switching frequency of battery can be very high. What should be the approach to this problem?
 
Physics news on Phys.org
  • #2
y33t said:
... so the switching frequency of battery ...

Huh? WHAT "switching frequency" of a battery? I don't understand what you mean.
 
  • #3
Smallest possible charge is 1 electron thus there should be some sort of rate to generation/conversion.
 
  • #4
rate to generation/conversion of what ?
 
  • #5
davenn said:
rate to generation/conversion of what ?

Ion transport rate.
 
  • #6
y33t said:
Ion transport rate.

Let join the chorus here: what ion transport?!

By now, you should have a sense that you are not explaining yourself very well here. The first 3 responses are us trying to figure out what exactly it is that you are talking about.

So how about starting all over again and put some effort into framing this as best as you can.

Zz.
 
  • #7
ZapperZ said:
Let join the chorus here: what ion transport?!

By now, you should have a sense that you are not explaining yourself very well here. The first 3 responses are us trying to figure out what exactly it is that you are talking about.

So how about starting all over again and put some effort into framing this as best as you can.

Zz.

I am sorry, trying again.

When you connect a resistive load across terminals of a battery, a direct current will start flowing ; meaning specific amount of electrons propogating per crosssection but how about the repetition rate of this process? Inside the battery ions are being transported and there is a rate of this phenomena.
 
  • #8
y33t said:
I am sorry, trying again.

When you connect a resistive load across terminals of a battery, a direct current will start flowing ; meaning specific amount of electrons propogating per crosssection but how about the repetition rate of this process? Inside the battery ions are being transported and there is a rate of this phenomena.

This ion transfer rate is equal to the rate of electrons flowing through the circuit between the terminals of the battery. If it wasn't a net charge would build up and prevent any further current flow from one terminal to the other.

Note that there is no switching involved here. The ions do not flow through the circuit, but through the electrolyte.

From wiki: http://en.wikipedia.org/wiki/Electrochemical_cell

As electrons flow from one half-cell to the other, a difference in charge is established. If no salt bridge was used, this charge difference would prevent further flow of electrons. A salt bridge allows the flow of ions to maintain a balance in charge between the oxidation and reduction vessels while keeping the contents of each separate.
 
  • #9
Drakkith said:
This ion transfer rate is equal to the rate of electrons flowing through the circuit between the terminals of the battery. If it wasn't a net charge would build up and prevent any further current flow from one terminal to the other.

Note that there is no switching involved here. The ions do not flow through the circuit, but through the electrolyte.

From wiki: http://en.wikipedia.org/wiki/Electrochemical_cell

Thank you for the information.
 
  • #10
y33t said:
What might be the explanation for this? electrons are being generated by a chemical process in battery and these reactions are very fast so the switching frequency of battery can be very high. What should be the approach to this problem?
The transitions within a battery at the atomic level happen at a very fast rate and they overlap. There aren't any real world instruments sensitive and fast enough to see the very slight and very fast flucuations in the output of a battery. From a practical standpoint, the output of a battery can be considered to be continous.
 
  • #11
That's what I was talking about but didn't wanted to push more after I observed that I could'nt express myself to majority efficiently.

The main phenomena responsible is;
http://wikipedia.org/wiki/Proton_coupled_electron_transfer

And it's being driven sequentally, but they overlap as you say and that's the main problem. If you study the problem further you are going to realize that there exists some sort of 'switching' indeed, and it should be around on the orders of ~E+24 due to fundamental properties of Weak Interaction.

Maybe this problem can be modeled using QM more precisely, approach should be right.

As of today, mankind is on the orders of E-18 which is far from probing E-24.

Thank you.
 
  • #12
y33t said:
And it's being driven sequentally, but they overlap as you say and that's the main problem. If you study the problem further you are going to realize that there exists some sort of 'switching' indeed, and it should be around on the orders of ~E+24 due to fundamental properties of Weak Interaction.

1. What is this switching problem?

2. I don't see how the weak interaction applies in this situation.
 
  • #13
1.No problem, solved.
2.I can't say that I understand fully either. But I can say that it's much faster than emf because can't see the propagation delay between electrolytes. Distance between them is 6cm so it would take 200ps minimum, I have a scale of 40ps on my scope but still get a phase difference of 0.
 
  • #14
y33t said:
1.No problem, solved.
2.I can't say that I understand fully either. But I can say that it's much faster than emf because can't see the propagation delay between electrolytes. Distance between them is 6cm so it would take 200ps minimum, I have a scale of 40ps on my scope but still get a phase difference of 0.

I can confidently say that the weak interaction has nothing to do with this.
 
  • #15
And on that note, this thread is done.

Zz.
 

Related to Examining DC Signals & Batteries: What's the Difference?

1. What is the difference between DC signals and batteries?

DC signals are electrical currents that flow in one direction, while batteries are devices that convert chemical energy into electrical energy. In other words, DC signals refer to the type of electrical current, while batteries refer to the source of that current.

2. How do DC signals and batteries work?

DC signals are created by a direct current (DC) power supply, which converts AC signals into a steady flow of electricity in one direction. Batteries, on the other hand, use a chemical reaction to produce a flow of electrons, creating an electric current.

3. Can DC signals be stored like batteries?

No, DC signals cannot be stored in the same way as batteries. DC signals are usually used for immediate use, while batteries are designed to store energy for later use.

4. Are there any differences in the way DC signals and batteries are measured?

Yes, there are differences in the way DC signals and batteries are measured. DC signals are typically measured in terms of voltage (V) and current (A), while batteries are measured in terms of voltage and capacity (Ah or mAh).

5. What are the main applications for DC signals and batteries?

DC signals are commonly used in electronic circuits, such as power supplies and audio equipment. Batteries are used to power a wide range of devices, including portable electronics, vehicles, and backup power systems.

Similar threads

  • Introductory Physics Homework Help
Replies
3
Views
303
  • Introductory Physics Homework Help
Replies
4
Views
326
Replies
34
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
1K
  • Other Physics Topics
Replies
20
Views
3K
Replies
19
Views
4K
Replies
17
Views
1K
Replies
14
Views
1K
  • Electrical Engineering
Replies
21
Views
6K
  • Introductory Physics Homework Help
Replies
1
Views
1K
Back
Top