# The Length of the Bridge, which a Train 130 Meters Long and Travelling at 45 km/hr Can Cross in 30 Seconds is?

### Computer MCQs Series for PPSC, FPSC – Most Repeated MCQs | Set 6

What are you looking for? Let’s dig in quickly

Recommended

## Explanation

The length of the bridge, which a train 130 meters long and travelling at 45 km/h can cross in 30 seconds will be determined according to the formula mentioned here under as;

Length = speed x time ________ (i)

Assuming the length of the bridge = b

Total length = b + 130

Speed will be converted to m/sec and time is also given (30 sec).

By substituting all the value in the equation (i); length becomes 245 meter.

## To Find

Length of the bridge = ?

## Solution

Given speed = 45 km/h

Speed in m/sec = (45 x 1000)/3600

Speed in m/sec = 12.5 m/sec

Let suppose

the length of bridge = b

so, total length = b + 130

Now,

length = speed x time

b + 130 = 12.5 x 30

b = 375 – 130

### Conclusion

The length of the bridge will be 245 meter, if a train 130 meters long and travelling at 45 km/hr crosses the said bridge in 30 seconds.