A passenger locomotive 200 meters long tracks at 90 km/h. How many seconds will it take to pass a bridge 350 meters long? MCQ with Answer and Explanation

Explanation:
Let car speed be c, then train speed is 1.25c. Time difference = 150/c - 150/(1.25c) = 15/60 hour = 1/4 hour. 150/c * (1 - 1/1.25) = 1/4 => 150/c * (0.25/1.25) = 1/4 => 150/c * (1/5) = 1/4 => 30/c = 1/4 => c = 120 km/h.

Explanation:
Upstream speed = 16 / 4 = 4 km/h. Upstream Speed = Speed in still water - Current speed => 4 = Speed in still water - 1 => Speed in still water = 5 km/h.

Explanation:
Speed = 120 / 6 = 20 m/s. In km/h = 20 * (18/5) = 72 km/h.