JEE Mains · Physics · STD 11 - 3.1 vectors
A vector \(\vec A \) is rotated by a small angle \(\Delta \theta\) radian \(( \Delta \theta << 1)\) to get a new vector \(\vec B\) In that case \(\left| {\vec B - \vec A} \right|\) is
- A \(\left| {\vec A} \right|\,\Delta \theta \)
- B \(\left| {\vec B} \right|\,\Delta \theta - \left| {\vec A} \right|\,\)
- C \(\left| {\vec A} \right|\,\left( {1 - \frac{{\Delta {\theta ^2}}}{2}} \right)\)
- D \(0\)
Answer & Solution
Correct Answer
(A) \(\left| {\vec A} \right|\,\Delta \theta \)
Step-by-step Solution
Detailed explanation
\(\begin{array}{l} Arc\,length\, = \,radius \times angle\\ So,\,\left| {\vec B - \vec A} \right| = \left| {\vec A} \right|\Delta \theta \end{array}\)
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