Faraday’s river-current apparatus uses two identical conducting plates of length a and width b on opposite sides of a river flowing with speed u. The plate separation is d and they are connected through load resistance R. If the vertical component of Earth’s magnetic field is Bᵥ and water resistivity is ρ, the load current is:

Question

G1 Physics · Accepted Answer

For a moving conductor, ε=∫(v⃗×B⃗)·dℓ⃗. Combine this with Ohm’s law and Lenz’s law where required. The result is Image 3.