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Question
A low voltage supply from which one needs high currents must have very low internal resistance. Why?
Solution
According to Ohm’s law, the relation for the potential is V = IR
Voltage (V) is directly proportional to the current (I).
R is the internal resistance of the source.
I = `"V"/"R"`
If V is low, then R must be very low, so that a high current can be drawn from the source.
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