Answer:
154.83 W
Explanation:
Applyying,
P = V²/R..................... Equation 1
Where P = power dissipated, V = voltage R = resistance
But,
R = Lρ/A................. Equation 2
Where L = length of the wire, A = crosssectional area, ρ = resistivity of the wire.
Substitute equation 2 into equation 1
P = V²/(Lρ/A)
P = AV²/Lρ........................ Equation 3
From the question,
Given: L = 30 cm = 0.3 m, ρ = 1.69 x 10⁻⁸Ω⋅m, V = 1 V.
But,
A = πd²/4, Where d = 1 mm
A = (3.14×0.001²/4) = 7.85×10⁻⁷ m²
Substitute these values into equation 3
P = (7.85×10⁻⁷×1²)/(0.3×1.69 x 10⁻⁸)
P = 154.83 W