JEE Mains · Maths · STD 12 - 10. vector algebra
Let \(\vec{a}, \vec{b}\) and \(\vec{c}\) be three vectors such that \(|\vec{a}|=\sqrt{3}\) \(|\overrightarrow{\mathrm{b}}|=5, \overrightarrow{\mathrm{b}} \cdot \overrightarrow{\mathrm{c}}=10\) and the angle between \(\overrightarrow{\mathrm{b}}\) and \(\overrightarrow{\mathrm{c}}\) is \(\frac{\pi}{3} .\) If \(\vec{a}\) is perpendicular to the vector \(\overrightarrow{\mathrm{b}} \times \overrightarrow{\mathrm{c}}\) then \(|\overrightarrow{\mathrm{a}} \times(\overrightarrow{\mathrm{b}} \times \overrightarrow{\mathrm{c}})|\) is equal to
- A \(34\)
- B \(36\)
- C \(30\)
- D \(38\)
Answer & Solution
Correct Answer
(C) \(30\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{\mathrm{b}} \cdot \overrightarrow{\mathrm{c}}=10 \Rightarrow 5|\overrightarrow{\mathrm{c}}| \cos \frac{\pi}{3}=10 \Rightarrow|\overrightarrow{\mathrm{c}}|=4\)…
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