A train 130 m long passes a bridge in 21 seconds moving at a speed of 90 Km/h. Find out the length o

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10 Dec 2021 Length of bridge

A train 130 m long passes a bridge in 21 seconds moving at a speed of 90 Km/h. Find out the length of the bridge

OPtion

1. 395 m.
2. 420 m.
3. 425 m.
4. 380 m.
5. 386 m.
6. 352 m.
7. 365 m.
8. 368 m.
9. 399 m.
10. None of the above

Solution

We have, speed of the train
= (length of the train + length of the bridge) / time taken in crossing the bridge
⇒ 5/18 x 90 = (130 + length of the bridge)/ 21
= 450 x 21 = 2340 + 18 (length of the bridge)
= 9450 – 2340 = 18 (length of the bridge)
∴ Length of the bridge
= 7110 / 18 = 395 m.

Correct Option: 1 Best Solution (6)

Pargat Pal Singh   2 years AGO

speed of train =90 kmph=90x5/18=25 m/sec
distance travelled by train in 21 secs= 21x25= 525 mtrs
length of bridge=525-130= 395 mtrs.. option 1

Like? Yes (5) | No   

A.P.Singh   2 years AGO

Train speed= 90 km/hr = 25 m/sec
length of bridge= 21*25 - 130 = 395 m

Like? Yes (4) | No   

RAMADURAI NATESAN   2 years AGO

Train speed = 90km/hr = 25m/s.
In 21s, distance covered =525m.
Bridge length = 525 - 130 = 395m

Like? Yes (1) | No (1)  

dhiraj prasad   2 years AGO

time =dist/speed
21= (130+x)/(90×5/18)
x= 395

Like? Yes (2) | No (2)  

Gowtham   2 years AGO

90(5/18)*21=135+X
X=395m

Like? Yes (2) | No (2)  

Varun   2 years AGO

900/36*21-130

Like? Yes (1) | No (3)