Answer:
the case is the one with the greatest current, L=15 cm , i = 2.19 10⁸ A
Explanation:
Ohm's law is
V = i R
Resistance is
R = ρ L / A
Where L is the length of the electrons pass and A the area perpendicular to the current
i = V / R
i = V (A / ρ L)
i = V / ρ (A / L)
We can calculate the relationship between the area and the length to know in which direction the maximum currents
Case 1
L = 0.15 m
A = 0.26 0.43 = 0.1118 m2
A / L = 0.1118 / 0.15
A / L = 0.7453 m
Case 2
L = 0.26 m
A = 0.15 0.43 = 0.0645 m2
A / L = 0.248 m
Case 3
L = 0.43 m
A = 0.15 0.26 = 0.039 m2
A / L = 0.0907 m
We can see that the case is the one with the greatest current, L=15 cm
Let's calculate the current
i = 5 / 1.7 10⁻⁸ (0.7453)
i = 2.19 10⁸ A
