Answer:

245 m is the track length

Verified answer

Answer :

• The length of the bridge is 245m.

Given :

• Length of train (l) = 130m
• Speed is train (v) = 45km/hr

To Find :

• The length of the bridge ?

Solution :

• Let the length of the bridge be x meter. First convert the speed into m/s units.

So,

➛ 1km/hr = 1000m/60 × 60s = 10/36m/s = 5/18m/s

➛ 45km/hr = 45 × 5/18m/s

➛ 45km/hr = 5 × 5/2m/s

➛ 45km/hr = 25/2m/s

• The total distance travelled by train is :

➛ L = l + x

➛ L = (130 + x)m

Using formula,

• v = L/t

Find the value of x, substituting the given values

➛ 25/2 = (130 + x)/30

➛ 30 × 25 = 2(130 + x)

➛ 750 = 260 + 2x

➛ 750 - 260 = 2x

➛ 490 = 2x

➛ x = 490/2

➛ x = 245

Hence,

• The length of the bridge is 245m.