Question

pls solve this(physics) JEE material#2018​

Answer 1

So the Effective speed/Velocity between train and bullet will be ( 5+10 = 15 m/s, since both are moving in opposite directions)

so if it takes 8 seconds to cross,

Then length of train is 8*15 = 120 meters

Answer 2

Relative Speed = V1+V2

= 5m/s + 10m/s = 15 m/s

Time = 8sec

Speed = Distance / Time

Distance = Speed x Time

= 15m x 8 s

DISTANCE = 120 meters

HOPE THIS WILL HELP YOU.