A ship \(A\) is moving westward with a speed of \(10~\text{kmph}\) and a ship \(B,\) \(100 ~\text{km}\) south of \(A,\) is moving northward with a speed of \(10~\text{kmph}.\) The time after which the distance between them becomes the shortest is:
1. \(0~\text{h}\) 
2. \(5~\text{h}\) 
3. \(5\sqrt{2}~\text{h}\) 
4. \(10\sqrt{2}~\text{h}\) 

Subtopic:  Relative Motion |
 51%
From NCERT
NEET - 2015
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Two particles \({A}\) and \({B}\), move with constant velocities \(\vec{v}_1\) and \(\vec{v}_2\) respectively. At the initial moment, their position vectors are \(\vec{r}_1\) and \(\vec r_2\) respectively. The conditions for particles \({A}\) and \({B}\) for their collision will be:

1. \(\dfrac{\vec{r}_1-\vec{r}_2}{\left|\vec{r}_1-\vec{r}_2\right|}=\dfrac{\vec{v}_2-\vec{v}_1}{\left|\vec{v}_2-\vec{v}_1\right|}\)
2. \(\vec{r}_1 \cdot \vec{v}_1=\vec{r}_2 \cdot \vec{v}_2\)
3. \(\vec{r}_1 \times \vec{v}_1=\vec{r}_2 \times \vec{v}_2\)
4. \(\vec{r}_1-\vec{r}_2=\vec{v}_1-\vec{v}_2\)

Subtopic:  Relative Motion |
 72%
From NCERT
NEET - 2015
To view explanation, please take trial in the course.
NEET 2026 - Target Batch - Vital
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To view explanation, please take trial in the course.
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