Question

A train 40m longpasses over a bridge 200m
Long at a speed of 36 km/h - How Long will it
to pass competely over the bridge?​

Answer 1

Answer:

24 seconds

Explanation:

Given:

Length of train = 40 metres

Length of bridge = 200 metres

Speed of train = 36 km/h

36 km/h = $36 \times \frac{5}{18}$ = $10 m/s$

To find:

Time taken to completely cross the bridge

We need to cross the full distance as the train needs to travel full distance.

Total distance = 200+40= 240 metres

Time = $\frac{distance}{speed}$

Time = $\frac{240}{10}$

Time = $24 \ Seconds$

The time taken for the bridge to cross the bridge is equal to 24 seconds

Answer 2

Given :-

◆ Length of train = 40 m

◆ Length of bridge = 200m

◆ Speed = 36 km/h

To find :-

Time taken by train to completely pass over the bridge !

• Formula used !

$\bigstar{\boxed{\sf { Speed = \dfrac{Distance}{Time }}}}$

• Convert speed into m/s

$\sf \implies 1\ km/h= \dfrac{5}{18} m/s\\ \\ \implies\sf \cancel{36}\times \dfrac{5}{\cancel{18}}\\ \\ \implies\sf 2\times 5 = 10m/s\\ \\ \implies{\boxed{\sf{ \ speed = 10m/s}}}$

• Now calculate the Distance
• Total distance

$\sf \bullet Distance = length \ of \ train +length \ of \ bridge \\ \\ \implies \sf Distance = 40m+ 200m\\ \\ \implies {\boxed{\sf{Distance = 240m}}}$

$\underline{\sf{\dag \ Time ?}}$

$\implies\sf Speed = \dfrac{Distance }{Time }\\ \\ \implies\sf 10 = \dfrac{240}{Time}\\ \\ \implies\sf 10\times Time = 240\\ \\ \implies\sf Time =\cancel{\dfrac{240}{10}}\\ \\ \implies\sf Time = 24 \ sec$

$\underline{\textsf{\textbf{\dag\ \ Time \ taken \ to\ completely\ pass \ over \ the \ bridge= 24 \ seconds }}}$