\nRoughly speaking, 12 gauge wire has 1.6 times the resistance of 10 gauge. That’s not too surprising, since lower gauge means bigger diameter, and electricity prefers to travel down a big wire compared to a small one, all else being the same.<\/p>\n
\nLet’s imagine a 50-ft extension cord (15.2m). It’s actually 100 ft, including the return wire to the socket, so that’s 30.4m. If it’s 12 gauge, its resistance will be 0.16 ohms; for 10 gauge, 0.10 ohms.<\/p>\n
\nThe tool itself might develop 1200W, which means it draws 10A at 120V (ideally). Therefore, its effective resistance might be about 12 ohms, since R = V\/I.<\/p>\n
Adding the line resistance from the extension cord, the total resistance is 12.16 ohms for the 12 gauge, while it’s 12.10 ohms for the 10 gauge.<\/p>\n
\nSince useful power is given by P=I2<\/sup>R (where R is the resistance of the device, not the line), and I=V\/Rtotal<\/sub>, the tool on the 12 gauge line might realize around (120\/12.16)^2*12, or 1169W. The one on the 10 gauge line might realize (120\/12.1)^2*12, or 1180W.<\/p>\n \nOne wonders – could someone familiar with the tool notice that power difference? (I suspect it’s possible).<\/p>\n Source:<\/p>\n toolsowner.com<\/a><\/p>\n hyperphysics.phy-astr.gsu.edu<\/a><\/p>\nJack of Oracle Tutoring by Jack and Diane,<\/a> Campbell River, BC.\n","protected":false},"excerpt":{"rendered":" Self-tutoring about working with corded tools: the tutor looks into how the extension cord’s gauge might affect performance. Roughly speaking, 12 gauge wire has 1.6 times the resistance of 10 gauge. That’s not too surprising, since lower gauge means bigger …<\/p>\n