Learn What is meant by Speed and How to Calculate the Motion or Speed by going through the entire article. Check out Formula to find the Speed of a Train when Train Passes through a Stationary Object and Train Passing through a Stationary Object of Certain Length. We have mentioned Solved Examples explaining step by step for a better understanding of the concept. Learn about Time and Distance Concepts too from here and get a good hold of the concept by practicing the sample problems available on a regular basis.
How to find the Speed of a Train?
There are two different scenarios to calculate the Speed of a Train. We explained each scenario in detail by taking a few examples. Understand the concept behind them easily. They are as under
- Train Passes through a Stationary Object
- Train Passes through a Stationary Object having Some Length
When a Train Passes through a Stationary Object
Consider the length of the train along with the engine be x. When the end of the train passes the object then the engine of the train travels the distance equal to the train length.
Time taken by train to pass the stationary object = length of the train/speed of the train
When a Train Passes through a Stationary Object having Some Length
When the end of the train passes the stationary object having a certain length, then the engine of the train moves a distance equal to the sum of both the length of the train and the stationary object.
Time taken by the train to pass stationary object = (length of the train+length of the stationary object)/speed of the train
Solved Examples on Speed of a Train
1. Find the time taken by a train 125 m long, running at a speed of 108 km/hr in crossing the pole?
Solution:
Length of the Train = 125m
Speed of Train = 108 km/hr
= 108*5/18
= 30 m/sec
Time taken by train to cross the pole = 125m/30m/sec
= 4.1 sec
2. A train 320 m long is running at a speed of 60 km/hr. what time will it take to cross a 160 m long tunnel?
Solution:
Length of the train = 320m
Length of the tunnel = 160m
Length of Train+Length of Tunnel = (320+160) = 480m
Speed of train = 60 km/hr
= 60*5/18
= 16.66 m/sec
Time taken by train to cross the tunnel = 480m/16.66m/sec = 28.8 sec
3. A train is running at a speed of 75 km/hr. if it crosses a pole in just 15 second, what is the length of the train?
Solution:
Speed of the train = 75 km/hr
Speed of the train = 75 × 5/18 m/sec = 20.83 m/sec
Time taken by the train to cross the pole = 15 seconds
Therefore, length of the train = 20.83 m/sec × 15 sec = 312.5 m
4. A train 250 m long crosses the bridge 120 m in 20 seconds. Find the speed of the train in km/hr?
Solution:
Length of the train = 250m
Length of the Bridge = 120 m
Total Length = Length of Train + Lenth of Bridge
= 250+120
= 370 m
Time taken to cross the bridge = 20 seconds
Speed of the Train = Length/Time = 370m/20 sec = 18.5 m/sec
To convert m/sec to km/hr multiply with 18/5
Speed of the Train in km/hr = 18.5*18/5
= 66.6 km/hr
Therefore, the speed of the train is 66.6 km/hr