# Current Entering And Leaving Battery

• harshraj216
Have you actually measured this lack of current, you claim? Are you including the self capacitance of the battery? Some charge will still flow to the unconnected terminal.

#### harshraj216

Why the current entering and leaving the battery in an elctirc circuit needs to be same??please provide a mathematical proof for this.
thanks

harshraj216 said:
Why the current entering and leaving the battery in an elctirc circuit needs to be same??please provide a mathematical proof for this.
thanks

Hi harshraj216 and welcome to Physics Forums!

Mathematical proofs are for mathematics. This is a physics/electronics question. Are you thinking of Kirchhoff's circuit laws? Please provide more info what you are thinking about.

Electrons do not "pool" any where, every electron that leaves the battery must return. Where else is there for it to go? Since current is electron flow, current out must equal current in.

It is not really impossible. Bring one pole of an isolated battery close to a charged vandegraafgenerator, while keeping the battery in your hand, and making sure your hand is earthed. When the spark occurs, a current pulse will be entering the first pole of the battery while there is no current leaving at the other pole.
This also applies if you connected the poles of the battery by a high resistance (a simple 'electrical circuit'). The resistance should be high compared to the impedance for the current pulse to your hand.

Orthoceras said:
It is not really impossible. Bring one pole of an isolated battery close to a charged vandegraafgenerator, while keeping the battery in your hand, and making sure your hand is earthed. When the spark occurs, a current pulse will be entering the first pole of the battery while there is no current leaving at the other pole.
This also applies if you connected the poles of the battery by a high resistance (a simple 'electrical circuit'). The resistance should be high compared to the impedance for the current pulse to your hand.

Have you actually measured this lack of current, you claim? Are you including the self capacitance of the battery? Some charge will still flow to the unconnected terminal.
A good justification why current is maintained is that, when more charge flows onto an object than flows off it, the forces on the charges rapidly become very high. Just work out the Coulomb force that is needed to bring two Unit (1 Coulomb) charges (say on two spheres) to within a unit (1metre) distance of each other. See this reference It is not at all surprising that significant charges do not bunch up in odd locations, like one end of a battery.
Any object can acquire a small unbalanced charge, the PD needed to charge it is Q/C, where Q is the charge and C is the capacity in Farads. Bear in mind that, until the recent introduction of 1F supercapacitors, the maximum value of available capacitors was around0.001F, that the capacitance of an object as big as the Earth is only about 700μF and that a Van der Graaff ball is about 20pF. No wonder it's hard to store much charge at all, if you are limited to reasonable values of voltage.

## 1. What is current entering and leaving a battery?

Current entering and leaving a battery refers to the flow of electric charge into and out of a battery. When a battery is being used, the current flows out of the positive terminal and into the negative terminal. When a battery is being charged, the current flows in the opposite direction, entering through the negative terminal and leaving through the positive terminal.

## 2. How does current entering and leaving a battery affect its performance?

The amount of current entering and leaving a battery is directly related to its performance. A higher current entering the battery means it is being drained faster, while a lower current entering the battery means it is being used at a slower rate. Similarly, a higher current leaving the battery during charging means it is being charged faster, while a lower current leaving the battery means it is being charged at a slower rate.

## 3. What factors can affect the current entering and leaving a battery?

The current entering and leaving a battery can be affected by various factors such as the type and size of the battery, the load or device it is powering, the temperature, and the age of the battery. Higher loads or larger devices will require more current, while extreme temperatures and older batteries may result in lower currents entering and leaving the battery.

## 4. Can the current entering and leaving a battery be measured?

Yes, the current entering and leaving a battery can be measured using an ammeter, which is a device that measures the flow of electric current. It can be connected in series with the battery to measure the current entering or leaving, or it can be connected in parallel to measure the total current flowing through the battery.

## 5. What happens if the current entering and leaving a battery is not balanced?

If the current entering and leaving a battery are not balanced, it can lead to issues with the battery's performance and lifespan. For example, if the current entering the battery is higher than the current leaving, it can cause the battery to overcharge and potentially damage it. On the other hand, if the current leaving the battery is higher than the current entering, it can cause the battery to drain too quickly and potentially shorten its lifespan.