Question

how much time will it train 192m long to cross a tunnel of land 328 long if it is running at a speed of 72 km per hour?
a) 26 sec
b) 46 sec
c) 36 sec
d) 28 sec​

Answer 1

Given info : speed of train = 72 km/h , length of tunnel = 328 m and length of train = 192 m

To find : time taken to cross the tunnel by train

Solution : total distance covered by train to cross the tunnel = length of train + length of tunnel

= 192 m + 328 m = 520 m

speed of train = 72 km/h = 72 × 5/18 = 20 m/s

time taken to cross the tunnel = distance covered/speed of train

= 520/20 = 26 sec

Therefore time taken by train to cross the tunnel is 26 sec. Option (A) is correct

Answer 2

Given:

• Length of train = 192 m
• Length of tunnel = 328 m
• Spped of train = 72 km/h = 72 × 1000/3600 = 20 m/s

To find:

• Time to cross the tunnel = ?

Soltuion:

》Total distance covered by the train = length of train + length of tunnel

=> 192 + 328

=> 520 meters

♧ Speed = distance / time ♧

》 Time = Distance / speed

=> 520 / 20

=> 26 s

☆ ☑ Option (a) is the right ans ☑ ☆

Hence, we get the required ans

Hope it helped you dear...