# Train $A$ and train $B$ are running on parallel tracks in the opposite directions with speeds of $36 \mathrm{~km} /$ hour and 72 $\mathrm{km} /$ hour, respectively. A person is walking in train $A$ in the direction opposite to its motion with a speed of $1.8$$\mathrm{km} / hour. Speed \left(\right. in \left.\mathrm{ms}^{-1}\right) of this person as observed from train B will be close to : (take the distance between the tracks as negligible) Question: Train A and train B are running on parallel tracks in the opposite directions with speeds of 36 \mathrm{~km} / hour and 72 \mathrm{km} / hour, respectively. A person is walking in train A in the direction opposite to its motion with a speed of 1.8$$\mathrm{km} /$ hour. Speed $\left(\right.$ in $\left.\mathrm{ms}^{-1}\right)$ of this person as observed from train $B$ will be close to : (take the distance between the tracks as negligible)

1. $29.5 \mathrm{~ms}^{-1}$

2. $28.5 \mathrm{~ms}^{-1}$

3. $31.5 \mathrm{~ms}^{-1 \mathrm{q}}$

4. $30.5 \mathrm{~ms}^{-1}$

JEE Main Previous Year Single Correct Question of JEE Main from Physics Motion in a Straight Line chapter.

JEE Main Previous Year 2 Sep. 2020 (I)

Correct Option: 1

Solution:

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