Question

A train 100m long is to cross a river bridge of lenght 800m. what time will it takes to cross the bridge? Given that the train moves with a constant velocity of 36km/h​

Answer 1

Hope it helps you......

Answer 2

$\huge\underline{\underline{\bf \orange{Question-}}}$

A train 100m long is to cross a river bridge of lenght 800m. what time will it takes to cross the bridge? Given that the train moves with a constant velocity of 36km/h

$\huge\underline{\underline{\bf \orange{Solution-}}}$

$\large\underline{\underline{\sf Given:}}$

• Lenght of train = 100m
• Lenght of bridge = 800m
• Speed ( v ) = 36km/h

Convert it in m/s

$\implies{\sf 36×\dfrac{5}{18}}$

$\implies{\sf \dfrac{180}{18}}$

$\implies{\bf v= 10m/s }$

$\large\underline{\underline{\sf To\:Find:}}$

• Time taken by train to cross the bridge ( t )

Distance covered in crossing bridge completely (s) = Length of train + Lenght of bridge

$\implies{\sf s =100+800 }$

$\implies{\sf s = 900m}$

$\large{\rm We \: know \: that- }$

✪$\large{\boxed{\bf \blue{Speed=\dfrac{Distance}{Time}}}}$

$\implies{\sf 10=\dfrac{900}{t} }$

$\implies{\sf t = \dfrac{900}{10}}$

$\implies{\bf \red{Time\:(t)=90\:s} }$

$\huge\underline{\underline{\bf \orange{Answer-}}}$

Time taken by train to cross the bridge is ${\bf \red{90s}}$.