I have a physics question

Question

A train is crossing a bridge across a chasm. but the track has a hole in it. (No funding for infrastructure). If the train is 818 m above the ground and it lands 381 m from the edge of the chasm, then how fast was it moving horizontally before falling

Answer 1

We must assume that the train starts to fall as it begins to pass over the chasm. Find the duration of the fall from Δy = v₀ t + 1/2 a t², where for y, v₀ = 0 before beginning to fall; -818 = 0 - 9.8/2 t², 4.9 t² = 818, and t = 12.9 s. Then Δx = v_x t, 381 = 12.9 v_x and v_x = 29.5 m/s.