Two cities are 150 km apart. Electric power is sent from one city to the other through copper wires. The fall of potential across wires is 8 V and the average resistance per kilometre is 0.5 Ω. The power loss in the wire is:
Options

Question

Two cities are 150 km apart. Electric power is sent from one city to the other through copper wires. The fall of potential across wires is 8 V and the average resistance per kilometre is 0.5 Ω. The power loss in the wire is:

Options

G1 Physics · Accepted Answer

Step 1: For two-wire loop, length = 2 × 150 = 300 km. Total resistance R = 300 × 0.5 = 150 Ω. Step 2: I = ΔV/R = 8/150 A. Step 3: Pₗₒₛₛ = (ΔV)²/R = 64/150 ≈ 0.427 W. Step 4: This differs from printed answer, so check source distance and resistance before publishing.