Question

A 90m long train, travelling at 45km/h, can cross a tunnel in 21sec. Fins the length of the tunnel​

Answer 1

Answer:

The length of tunnel is 90 m

Step-by-step explanation:

Let the length of tunnel be x

Length of train = 90 m

Total distance = 90+x

Speed of train =48 km/hr = 48 \times \frac{5}{18}=\frac{40}{3} m/s48km/hr=48×

18

5

=

3

40

m/s

Time = 21 s

Time = \frac{Distance}{Speed}Time=

Speed

Distance

21 = \frac{90+x}{\frac{40}{3}}21=

3

40

90+x

21 \times 40 =3(90+x)21×40=3(90+x)

840=270+3x840=270+3x

570=3x570=3x

\frac{570}{3}=x

3

570

=x

190=x

Hence the length of tunnel is 90 m

#Learn more:

A train 77m long is running at 60 km/hr if it takes 30 seconds to cross the tunnel then find the length of the tunnel

Step-by-step explanation:

i hope it's helpful to you

Answer 2

Answer:

1.68km or 1680 meter , length of the tunnel