Circuits and electric heating?

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Circuits and electric heating?

For ease of installation, a cabin that is used occasionally is supplied with baseboard electric heating. These are 30 amp circuits powered with 220 volts. To supply 70,000Btu/h (about 20kW), how many circuits are needed? What is the resistance of each baseboard "strip" in a single circuit?

I need help with this problem... I can't figure it out at all.

2007-02-28 14:34:22 · 1 answers · asked by Sir Guitarist 2 in Science & Mathematics ➔ Engineering

1 answers

70,000 Btu/hr is 20,510 Watts. The strips are 30 * 240 = 7,200 Watts each (240V is the standard, not 220). So 3 strips would be 21.6 kW. The resistance would be Power / I^2, 7200/900 = 8 Ohms.

2007-02-28 14:49:12 · answer #1 · answered by Joe 5 · 0⤊ 0⤋