Refer to the circuit diagram shown in the paper. The heat generated in the 6 Ω resistor during 100 s is α /100 J. Find the nearest integer value of α.

Question

G1 Physics · Accepted Answer

Choose the right-hand node as zero potential and let the central junction have potential x volts, using the source polarities shown in the figure. Applying Kirchhoff's current law at the junction gives (x-3) ÷ 6 + (x-2) ÷ 3 + x ÷ 4 = 0. Multiplying by 12: 2(x-3)+4(x-2)+3x = 0. Thus, 2x-6+4x-8+3x = 0, 9x = 14, x = 14 ÷ 9 V. The magnitude of current through the 6 Ω resistor is I = |x-3| ÷ 6 = |14 ÷ 9 - 3| ÷ 6 = 13 ÷ 54 A. Heat generated in 100 s: H = I²Rt = (13 ÷ 54)²×6×100 ≈ 34.7737 J. Given H =…