Appliance A is rated at 1200W for operation on a 120V circuit, whereas appliance B is rated at 300W for the same supply voltage. A student claims that thinner household wiring would be safe for appliance B because “lower power means less risk of overheating.”
(a) Describe qualitatively how the current drawn by an appliance depends on its power rating when the supply voltage is fixed.
(b) Using appropriate reasoning that cites physical relationships among electrical quantities, evaluate the student’s claim about wire thickness for appliance B.
(c) Identify one additional factor, other than the magnitude of the current, that a residential electrician must consider when selecting the gauge (thickness) of wiring for a household circuit and explain its relevance.