10.1 Motional emf. Two trains approach each other at velocities v1 and v2 as shown in Figure 10.37. Assume the trains’
axles are good conductors and the rails have a resistance r [Ω/km]. Use d ¼ 2 m. The trains are P ¼ 10 km apart. Also
given: v1 ¼ 100 km/h, v2 ¼ 120 km/h, r ¼ 0.1 Ω/km. The vertical component of the terrestrial magnetic flux density is
B0 ¼ 0.05 mT. Calculate:
(a) The current in the rails produced by the motion of the trains in the terrestrial magnetic flux density at the instant
shown in Figure 10.37.
(b) The current in the rails as a function of time taking t ¼ 0 at the instance shown in Figure 10.37.