1. The problem statement, all variables and given/known data An airplane with a wingspan W = 30 m is flying due north at v = 672 km/h. The Earth's field is 1.210-4 T, due north and inclined q = 42 below horizontal. What is the magnitude of the potential difference between the ends of the wings? http://media.apexlearning.com/Images/200408/06/ba941605-5eb4-4e21-a8eb-b2cb82a7c95e.gif 2. Relevant equations Magnetic flux: φ = B · A · cosθ Induced potential difference (emf) due to a changing magnetic field: V = -N · ∆φ/∆t Motional emf: V = -B · L · v Could be any one of these. Also, the problem said to treat it like pulling a rectangular wire through a magnetic field, and find the area facing the field using the angle. 3. The attempt at a solution It seems this is more of a riddle than a problem. How do I find the area facing the magnetic field? I'm only given the wingspan!