What is current of electric circuit which has only one component a battery (or cell)? Explain why.
closed as not a real question by Emilio Pisanty, Manishearth♦ Dec 18 '12 at 17:59
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Initially it is the voltage of the battery divided by it's internal resistance (plus that of the conductor completing the circuit across the battery terminals). Because of Ohms Law
The Internal resistance of a battery depends on its chemistry, construction, current, temperature and other factors. As the energy stored in the battery is converted to heat, the internal resistance will change. Since batteries are not designed to be in a circuit with no other components, it is very likely the battery will quickly fail, for example the electrolyte may boil.
It is this type of experiment that helps to keep our gene-pool healthy.
You don't have a one component system because batteries are not ideal. You can replace the battery with a (theoretical) "ideal" voltage source or a (real) super conducting capacitor.
If you use an "ideal" voltage source, the current will increase rapidly (not instantly because the wire has an inductance). It will continue to increase rapidly forever (well until the wire blows). Even theoretically, the current can't actually be "infinite" because electrons have a finite mass (E potential -> force on the charge -> a=f/m).
It's interesting to replace your battery with a perfect, superconducting capacitor because this is "doable" in a lab. Let's assume there are no losses (no parasitic losses, no restive losses). The wire "shorting" the capacitor has a finite, non zero, inductance. So you end up with an oscillator circuit, with a very high Q.