366236
If the vectors \(\overrightarrow A = 2\hat i + 4\hat j\) and \(\overrightarrow B = 5\hat i - p\hat j\) are parallel to each other, the magnitude of B is
1 \(5\sqrt 5 \)
2 \( - 10\)
3 \(15\)
4 \( - 4\,\hat i\)
Explanation:
If \(\overrightarrow A \;{\rm{and}}\;\overrightarrow B \) are parallel \(\vec A \times \vec B = 0\) \( \Rightarrow \hat k( - 2p - 20) = 0\) \(p = - 10\) \(\therefore \overrightarrow B = 5\hat i + 10\hat j\) \(\left| B \right| = \sqrt {25 + 100} \, = 5\sqrt 5 \)
366236
If the vectors \(\overrightarrow A = 2\hat i + 4\hat j\) and \(\overrightarrow B = 5\hat i - p\hat j\) are parallel to each other, the magnitude of B is
1 \(5\sqrt 5 \)
2 \( - 10\)
3 \(15\)
4 \( - 4\,\hat i\)
Explanation:
If \(\overrightarrow A \;{\rm{and}}\;\overrightarrow B \) are parallel \(\vec A \times \vec B = 0\) \( \Rightarrow \hat k( - 2p - 20) = 0\) \(p = - 10\) \(\therefore \overrightarrow B = 5\hat i + 10\hat j\) \(\left| B \right| = \sqrt {25 + 100} \, = 5\sqrt 5 \)
366236
If the vectors \(\overrightarrow A = 2\hat i + 4\hat j\) and \(\overrightarrow B = 5\hat i - p\hat j\) are parallel to each other, the magnitude of B is
1 \(5\sqrt 5 \)
2 \( - 10\)
3 \(15\)
4 \( - 4\,\hat i\)
Explanation:
If \(\overrightarrow A \;{\rm{and}}\;\overrightarrow B \) are parallel \(\vec A \times \vec B = 0\) \( \Rightarrow \hat k( - 2p - 20) = 0\) \(p = - 10\) \(\therefore \overrightarrow B = 5\hat i + 10\hat j\) \(\left| B \right| = \sqrt {25 + 100} \, = 5\sqrt 5 \)
366236
If the vectors \(\overrightarrow A = 2\hat i + 4\hat j\) and \(\overrightarrow B = 5\hat i - p\hat j\) are parallel to each other, the magnitude of B is
1 \(5\sqrt 5 \)
2 \( - 10\)
3 \(15\)
4 \( - 4\,\hat i\)
Explanation:
If \(\overrightarrow A \;{\rm{and}}\;\overrightarrow B \) are parallel \(\vec A \times \vec B = 0\) \( \Rightarrow \hat k( - 2p - 20) = 0\) \(p = - 10\) \(\therefore \overrightarrow B = 5\hat i + 10\hat j\) \(\left| B \right| = \sqrt {25 + 100} \, = 5\sqrt 5 \)