The batteries tag has no wiki summary.
10
votes
1answer
559 views
Does the mass of a battery's change when charged/discharged?
... and if so, how much? Is it possible to detect it, or is it beyond any measurement? I'd say there are two possible scenarios (depending on the battery type) and both seem interesting:
The battery ...
5
votes
2answers
158 views
What's the difference between Capacitors, Ultra-Capacitors and Batteries
Capacitors are known to hold and release energy very quickly, unlike the slower release that batteries exhibit. If one were to bunch many (1000's of) capacitors together could they function as a ...
4
votes
1answer
663 views
short circuit an alkaline battery
i'm not doing anything related to physics, but i'm just curious : What really happen when i short circuit an alkaline battery ? some article in the net shown that fire/explosion can be happened when ...
3
votes
2answers
454 views
If we charge a capacitor can we discharge it into a battery?
I have read that we can charge a capacitor using a battery, but can the vice versa happen? My project needs to show a battery being charged through a fully charged capacitor.
3
votes
2answers
215 views
How many grams of explosive are equivalent to the energy in a battery?
In the movie Terminator 3: Rise of the Machines, Arnie's fuel cells were twice shown to be extremely devastating when their stored energy was released.
In real life, how many grams of, say, gunpowder ...
3
votes
1answer
190 views
Lifetime of battery
If I directly connect two terminals of 3V battery (negative to positive) using copper wire, would it lose all its charge faster compared to another 3V battery that is used to lighten a 1.5V bulb?
3
votes
1answer
116 views
Path of an electron through an electric circuit
When a potential difference is applied across a conductor, and if an electron moves from the negative terminal of the battery and reaches the positive terminal, then I want to know if the electron ...
3
votes
2answers
82 views
How can a circuit function with two negative battery terminals facing each other?
Here is a drawing of the circuit that is confusing me:
I don't quite understand how batteries work in this diagram. If a battery has a negative and positive terminal, there must be a barrier ...
2
votes
5answers
3k views
What is the difference between a battery and a charged capacitor?
What is the difference between a battery and a charged capacitor?
I can see lot of similarities between capacitor and battery. In both these charges are separated and When not connected in a circuit ...
2
votes
2answers
130 views
Mechanical work to required battery power
I have a very practical question where I've calculated the mechanical work needed by a simple mechanical system by solving the line integral $W = \int_C \ F \ dx$. However, since I have a black spot ...
2
votes
2answers
68 views
Static discharge out of 3 volts button battery
I am starting to get interested in static electricity
I have found this which is very cool but I do not know how I can control the output voltage.
...
2
votes
1answer
80 views
Does recharging a battery at a lower temperature lower its internal resistance?
Does temperature affect the internal resistance of batteries? And does charging a "frozen" battery allow it to charge faster than a warm or room temperature battery?
1
vote
2answers
87 views
Simple ohms law on a battery ? Paradox or conceptual error?
Suppose we have a regular pencil battery which supplies DC voltage $V$. Say we take copper wire and connect the ends of the battery to an $R$ ohms resistance.
Then Ohm's law tells use the current in ...
1
vote
2answers
159 views
What is the volume of gases liberated when a battery is charged?
Apparently Hydrogen/Oxygen are liberated when a Lead-acid battery is charged.
If true, how does one calculate the expected volume & rate at which each gas is liberated when a battery is charged?
...
1
vote
2answers
43 views
Different batteries connected in parallel
If we have 2 batteries one of emf x and the other is of emf y and we connect them in series we get an effective emf of x+y.
But what if we connect them in parallel, how to calculate the emf now?
1
vote
2answers
624 views
Does the 'mAh' rating of a battery have something to do with its power?
I'm curious about the 'mAh' of a battery: how can this impact the power of the battery?
I've done some research on the internet, and most of the articles I found explain about the 'amount of charge ...
1
vote
3answers
78 views
Capacitor Charging and Discharging when connected to the ground
When we charge a capacitor using a battery and then remove the battery, the plates of capacitor becomes charged. One holds positive charge and the other one gets equal negative charge. o. k. ?
Now ...
1
vote
3answers
134 views
Can I charge a capacitor using 2 batteries?
1 capacitor, 2 separate batteries (Battery A and Battery B).
Connect A+ to one side of the capacitor and B- to the other side of the capacitor.
A and B are not connected, there is no closed circuit.
...
1
vote
2answers
90 views
How can you calculate (or convert) the Wh of a capacitor whose energy is given in Farads
When trying to compare the energy in a battery to the energy in a capacitor, the units don't match up. How can one compare a battery whose Ah are 10 and Voltage is 3 (for a total of 30 Wh) to a ...
0
votes
1answer
321 views
Calculate the UPS Capacity in amp-hours [closed]
I am trying to find out the UPS capacity in amp-hours for my HP UPS system.
I've already done some calculations based on the UPS information from the HP Power Manager software.
Bellow are my ...
0
votes
2answers
288 views
Can a battery charger be too powerful for a rechargeable battery?
I got the impression that a regular iPhone charger can charge the iPhone and the iPhone won't become too hot while charging, and the charging time is standard, but if using the 10W iPad charger to ...
0
votes
3answers
9k views
Charging 12V 150Ah battery
I want to charge a 12V battery of 150Ah with a solar panel. The solar panel specs is
12V, 25 Watt.
Can anyone please provide me how to calculate that how much time it will take to charge the battery? ...
0
votes
2answers
59 views
Why isn't this capacitor charging?
Let's say you have a parallel plate capacitor and you connect one plate to the positive terminal of a battery and the other plate to the negative end. So this is like a static situation, you have a ...
0
votes
1answer
117 views
Battery fully loaded, pull out the chord?
I recently bought a new phone (Samsung Galaxy 3) and when the battery is fully loaded, it says like "Battery fully loaded, pull out the chord".
Is this a typo from Samsung, or would there ...
0
votes
2answers
89 views
Does using batteries in a series raise the overall Wh's of the batteries used? Why/Why Not?
If one has 2 batteries of 6 Volts each with 500 mAh each, then separately the batteries should provide 6 Volts * 500 mAh = 3 Wh each or 6 Wh total. However would it be the case that if someone where ...
0
votes
2answers
89 views
What is a “gravitational cell”?
I am not a physicist, and I don't understand the details of electromagnetism. Anyhow, I was looking for how the batteries work in Google. So, I came across this article: "How batteries work: A ...
-1
votes
1answer
199 views
Can I use AA batteries to charge iPhone? [closed]
Technically, 4 AA batteries will give out ~5V, which is equivalent to USB. Can you use 4 AA batteries to charge an iPhone, without messing up the Li-Ion cells used on iPhone?
So my question really ...
