Question

A 100 meter long train moving with constant speed of 90 km/h crosses a tunnel of 300 meter long. The time taken by the train to cross the tunnel completely is

Answer 1

Speed of train $=90$ km/h and length of train $=100$m $=0.1$km

length of tunnel $=300m=0.3$km

Time taken to cross the tunnel completely $=\frac{0.3km+0.1km}{90km/h}$

$=\frac{0.4km}{90km/h}=\frac{40}{900}$hour $=0.044$ hour.