Question

Beth is taking the train to see her boyfriend on Valentine's Day! The train is hundred m long and it takes 30 seconds to cross a 400 m bridge. What speed is the train going at?

Answer 1

16.67 m/s.

Explanation:

We have been given that a train is 100 m long and it takes 30 seconds to cross a 400 m bridge.

We will use speed formula to solve our given problem.

`\text{Speed}=\frac{\text{Distance}}{\text{Time}}`

We know that train has to cover the length of bridge and its own length to fully cross the bridge.

`\text{Total distance covered by train}=\text{ Length of bridge+ Length of train}`

`\text{Total distance covered by train}=400\text{ m}+ 100\text{ m}`

`\text{Total distance covered by train}=500\text{ m}`

Time taken by train to cross the bridge = 30 seconds.

Upon substituting these values in speed formula we will get,

`\text{Speed}=\frac{500\text{ m}}{30\text{ seconds}}`

`\text{Speed}=16.67\frac{\text{ m}}{\text{ second}}`

Therefore, the trains is going at a speed of 16.67 meters per second.