MCQ
A $120\, m$ long train is moving in a direction with speed $20 \,m/s$. $A$ train $B$ moving with $30\, m/s$ in the opposite direction and $130\, m$ long crosses the first train in a time
- A$6\,s$
- B$36 \,s$
- C$38 \,s$
- ✓None of these
✓
Answer
Correct option: D.
None of these
d
(d) Total distance $ = 130 + 120 = 250\;m$
(d) Total distance $ = 130 + 120 = 250\;m$
Relative velocity $ = 30 - ( - 20) = 50\;m/s$
Hence $t = 250/50 = 5s$
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