Why are thick copper wires used as connecting wires?

Answer 1

-- Any energy dissipated by the conencting wires is lost from the circuit, and unavailable to do the job for which the circuit is intended. The less resistance the connecting wires have, the less energy they'll dissipate. So the connecting wires need to have as little resistance as possible.

-- Copper is easy to work, easy to form wires from, and is the second-best electrical conductor known, after silver. Copper is used instead of silver because it costs less.

-- The thicker any wire is, the less resistance it has.

Answer 2

Wires are measurements of their cross-sectional area and are expressed in gauge. In general, the smaller the conductor, the smaller the amount of current that can flow thru it. Conversely, the larger the conductor, the m ore current that can be carries by it.

Answer 3

Thicker wires have less resistance, and therefore less heat is created when a large current is passed through them. Thicker wires also tend to have less voltage drop over a longer run.