Suppose you have a 9 V battery that you connect to a load having a very low resistance (e.g. 0.1 ohm). From Ohm's law, the current would be I = V/R = 90 amps, which seems impossible to obtain from such a battery. If we suppose that the load will not burn, which of these options is the correct one?(adsbygoogle = window.adsbygoogle || []).push({});

1) The battery has a maximum power it can provide. For example, if this power is P = 100 W, then since P = RI^2 the current will be I = (P/R)^0.5 = 31.6 amps and the voltage V = RI = 3.16 V.

2) The battery has a maximum current it can provide. For example, if this current is I = 5 A, then V = RI = 0.5 V.

I am aware the values given for P and I might not be realist. I am just interested in the general behaviour of a battery (is current, power or voltage the fixed value?). Thanks for your help.

Bakshi

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# Homework Help: Maximum power/current for a battery?

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