Question

A low voltage supply from which one needs high currents must have very low internal resistance. Why?

Answer 1

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.