# Heat produced on breadboard power rails with 1 vs 2 loads

Lets say we have a 12V power source connected to a single load, and 2.4 amps go through this wire. The wire will heat up.

Now the same 12V source, but now there’s two loads, each pulling 1.2 amps each. Which will heat the wire more? Would each node absorb half of the heat? Assume we’re using roughly the same length of wire for each circuit. Like this:

My guess is that the heat will transfer through both nodes, resulting in the same temperature as if with just one single load.. And some background: This question came up during a discussion about breadboard power rails and pulling too much current through them.

• You probably meant 2R in the second schema, not 1/2R. Otherwise each node will draw twice the current, 4x more in total, than in the first schema. Now the important question: Are you asking about the heat of the wires, or the resistors? Feb 21, 2022 at 8:36
• Yes 2R. I’ll update it. I am asking about just the wire. Feb 21, 2022 at 16:44