JEE Mains · Physics · STD 11 - 3.1 vectors
Two particles are located at equal distance from origin. The position vectors of those are represented by \(\bar{A}=2 \hat{i}+3 n \hat{j}+2 \hat{k}\) and \(\bar{B}=2 \hat{i}-2 \hat{j}+4 p \hat{k}\), respectively. If both the vectors are at right angle to each other, the value of \(\mathrm{n}^{-1}\) is _____ .
- A 3
- B 5
- C 7
- D 9
Answer & Solution
Correct Answer
(A) 3
Step-by-step Solution
Detailed explanation
\begin{aligned} & \overrightarrow{\mathrm{A}} \cdot \overrightarrow{\mathrm{B}}=0 \\ & 4-6 \mathrm{n}+8 \mathrm{p}=0 \\ & |\overrightarrow{\mathrm{~A}}|=|\overrightarrow{\mathrm{B}}| \\ & 4+9 \mathrm{n}^2+4=4+4+16 \mathrm{p}^2 \\ & 9 \mathrm{n}^2=16 \mathrm{p}^2 \\ &…
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