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QAIPM-2015-Ph-1271: NEET 2015 Physics - Class 11 AIPM-2015-Ph-1271 Solution: Two particles A and B move with constant velocities \( {v}_1\)…

Two particles A and B move with constant velocities v⃗1\vec{v}_1 and v⃗2\vec{v}_2. At the initial moment their position vectors are r⃗1\vec{r}_1 and r⃗2\vec{r}_2 respectively. The condition for particles A and B for their collision is r⃗1⋅v⃗1=r⃗2⋅v⃗2\vec{r}_1 \cdot \vec{v}_1 = \vec{r}_2 \cdot \vec{v}_2 r⃗1×v⃗1=r⃗2×v⃗2\vec{r}_1 \times \vec{v}_1 = \vec{r}_2 \times \vec{v}_2 r⃗1−r⃗2∣r⃗1−r⃗2∣=v⃗2−v⃗1∣v⃗2−v⃗1∣\frac{\vec{r}_1-\vec{r}_2}{|\vec{r}_1-\vec{r}_2|} = \frac{\vec{v}_2-\vec{v}_1}{|\vec{v}_2-\vec{v}_1|} r⃗1−r⃗2=v⃗1−v⃗2\vec{r}_1 - \vec{r}_2 = \vec{v}_1 - \vec{v}_2

Multiple Choice Options

  • A r→1×v→1=r→2×v→2{\overrightarrow r _1} \times {\overrightarrow v _1} = {\overrightarrow r _2} \times {\overrightarrow v _2} r 1 _ _ v 1 _ = r 2 _ _ v 2 _
  • B r→1−r→2=v→1−v→2{\overrightarrow r _1} - {\overrightarrow r _2} = {\overrightarrow v _1} - {\overrightarrow v _2} r 1 _ _ r 2 _ = v 1 _ _ v 2 _
  • C r→1−r→2∣r→1−r→2∣=v→2−v→1∣v→2−v→1∣{{{{\overrightarrow r }_1} - {{\overrightarrow r }_2}} \over {\left| {{{\overrightarrow r }_1} - {{\overrightarrow r }_2}} \right|}} = {{{{\overrightarrow v }_2} - {{\overrightarrow v }_1}} \over {\left| {{{\overrightarrow v }_2} - {{\overrightarrow v }_1}} \right|}} _ r 1 _ _ r 2 _ _ r 1 _ _ r 2 _ _ = _ v 2 _ _ v 1 _ _ v 2 _ _ v 1 _ _
  • D r→1.v→1=r→2.v→2{\overrightarrow r _1}.{\overrightarrow v _1} = {\overrightarrow r _2}.{\overrightarrow v _2} r 1 _ . v 1 _ = r 2 _ . v 2 _

Step-by-Step Verified Solution

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