JEE Mains · Physics · STD 11 - Motion in straight line
- JEE Mains 2020
- Medium
- MCQ
Train \(A\) and train \(B\) are running on parallel tracks in the opposite directions with speeds of \(36\, km / hour\) and \(72 \,km / hour,\) respectively. A person is walking in train \(A\) in the direction opposite to its motion with a speed of \(1.8\, km / hr\). Speed (in \(ms ^{-1}\) ) of this person as observed from train \(B\) will be close to (take the distance between the tracks as negligible)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) \(29.5\)
Step-by-step Solution
Detailed explanation
Velocity of man with respect to ground
\(\overrightarrow{ V }_{m / g}=\overrightarrow{ V }_{ m / A }+\overrightarrow{ V }_{ A }=-1.8+36\)
Velocity of man w.r.t. \(B\)
\(\overrightarrow{ V }_{ m / s }=\overrightarrow{ V }_{ m }-\overrightarrow{ V }_{ B }\)
\(=-1.8+36-(-72)\)
\(=106.2 km / hr\)
\(=29.5 m / s\)
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