5. A train is running at the speed of 42 km/h.
If it crosses a pole in 20 s. Find the length
of the train
Answers
Answer:
Step-by-step explanation:
Think of this question a little differently.
The train is moving at a speed of 60 km/hr. Let's assume ourselves to be stationary in the train. Thus we will see the pole to be moving backwards at a speed of 60 km/hr.
Now the question, actually, is stating that the time taken by the pole to cover the distance equivalent to that of the length of the train is 9 sec.
Given speed = 60 km/hr.
60 km/hr = (60*1000 m) ÷ (1*3600 s)
=16.666 m/s
So the pole travels 16.66 m in 1 sec. Thus the distance travelled by the pole in 9 sec (i.e., the length of the train) = 16.666*9
=149.994 m (almost 150 m
Answer :
- Length of the train is 233.33m
Given :
- A train is running at the speed of 42km/h
- if it crosses a pole in 20 s
To find :
- The length of the train
Solution :
Given that,
Speed = 42km/h
● (42 × 5/18)m/s
● 35/3 m/s
Speed is 35/3 m/s
Now Given that , Time taken by train is 20s so ,
As we know that ,
- Distance = speed × time
● 35/3 × 20
● 233.33m
Hence , The length of the train is 233.33m
More Explanation :
- speed = distance/time
- Distance = speed × time
- Time = Distance/ speed