Question

 

The length of the bridge, which a train 130 metres long and travelling at 45 km/hr can cross in 30 seconds, is:

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Answer 1

Given;

• speed = 45km/h
• Speed( in m/s ) :

$45 \times \frac{5}{18} \\ 5 \times \frac{5}{2} \\ \frac{25}{2} m {s}^{ - 1}$

Thus distance covered in 30 seconds ;

s = d/t. then. d = s×t

$d \: = s \: \times t \\ d \: = \frac{25}{2} \times 30 \\ d \: = 25 \times 15 \\ d \: = 375m$

This distance is the total distance the train's end point covered. Thus 130m of the train is extra .

Therefore length of the bridge is ;

• 375 - 130
• 245 m

#answerwithquality

#BAL

Answer 2

Answer:

245 m

Step-by-step explanation:

Let, Length of Bridge = x m

Total Distance = ( x + 130 )m

Speed = 45 km/h

           = 45 * (5/18) m/s

           = 25/2 m/s

Time = 30 s

So,

Distance/Time = Speed

or, ( x + 130)/30 = 25/2

or, x = 245

.................Thanks..................