JEE Mains · Physics · STD 11 - 2. motion in straight line
A passenger sitting in a train A moving at \(90\,km / h\) observes another train \(B\) moving in the opposite direction for \(8\,s\). If the velocity of the train \(B\) is \(54\,km / h\), then length of train \(B\) is \(..........\,m\)
- A \(80\)
- B \(200\)
- C \(120\)
- D \(320\)
Answer & Solution
Correct Answer
(D) \(320\)
Step-by-step Solution
Detailed explanation
Velocity of train \(A\) \(V _{ A }=90 \frac{ km }{ hr }=90 \times \frac{5}{18}=25\,m / s\) Velocity of train \(B\) \(V _{ B }=54 \frac{ km }{ hr }=54 \times \frac{5}{18}=15\,m / s\) Velocity of train B w.r.t.…
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