Question

A 100 m long train crosses a 200 m long bridge at a speed of 90 Km/h. How much time will it take to cross the bridge completely?

Answer 1

Diagram :

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Answer:

• Length of Train = 100 m
• Length of bridge = 200 m
• So, Total Distance = Length of train + Length of bridge = 100 m + 200 m = 300 m
• Speed = 90 km/hr = 25 m/s

☯ $\underline{\boldsymbol{According\: to \:the\: Question\:now :}}$

$:\implies\sf Time = \dfrac{Distance}{Speed}$

$:\implies\sf Time = \dfrac{300}{25}$

$: \implies\underline{ \boxed{\textsf{ \textbf{ Time = 12 seconds}}}}$

$\therefore\underline{\textsf{The time will it take to cross the bridge completely is \textbf{12 seconds}}}.$