Question

A train 150 m long is running at a speed of 90 km/h. Find the time taken by the train
to cross a tree.​

Answer 1

☃️ Question :-

A train 150m long is running at a speed of . Find $\sf 90\dfrac{km}{hr}$ the time taken by the train to cross a tree.

☃️ Solution :-

• Length of the train = 150m = Distance
• Speed = $\sf 90\dfrac{km}{hr}$

Speed is to be converted into $\sf \dfrac{m}{s}$ from $\sf \dfrac{km}{hr}$

Thus, it has to multiplied by $\sf \dfrac{5}{18}$

$\red \mapsto \sf 90 \times \frac{5}{18}$

$\red \mapsto \sf \cancel{90}× \frac{5}{\cancel{18} }$

$\red \mapsto \sf 25 \frac{m}{s}$

We know that, $\sf \green {Speed=\dfrac{Distance}{Time}}$

$\implies \sf 25\dfrac{m}{s}=\dfrac{150m}{Time}$

$\implies \sf Time × 25 \frac{m}{s} =150m$

$\implies \sf Time = \frac{\cancel{150}m}{\cancel{25} \frac{m}{s} }$

$\implies \sf \pink {Therefore, \: time=6 \: seconds}$

Therefore, the time taken by the train is 6 seconds to cross the tree.

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Hope it helps :)