To determine the length of the train, we first need to convert the speed from kilometers per hour to kilometers per minute, since the time given is in minutes.
Speed of the train: 120 km/h
Speed of the train in km/min = (120 km/h) / 60 = 2 km/min
Now, we know that the train takes 5 minutes to completely emerge from the tunnel, and during this time, it travels a distance equal to the length of the tunnel.
Distance traveled by the train = Length of the tunnel = 9.5 km
Speed of the train = Distance traveled by the train / Time taken
2 km/min = 9.5 km / Time taken
Solving for Time taken:
Time taken = 9.5 km / 2 km/min = 4.75 min
Since the train takes 4.75 minutes to travel 9.5 km, we can conclude that the length of the train is equal to the distance it travels in this time.
Length of the train = Distance traveled by the train = 9.5 km
Therefore, the length of the train is 9.5 kilometers.