Question 201: Motion in 2D & Vectors

Question

If a vector $2\widehat i + 3\widehat j + 8\widehat k$ is perpendicular to the vector $4\widehat j - 4\widehat i + \alpha \widehat k,$ then the value of $\alpha $ is

Accepted Answer

For two vectors to be perpendicular to each
other
${\overrightarrow A .\overrightarrow B  = 0}$
$\left( {2\widehat i + 3\widehat j + 8\widehat k} \right).\left( {4\widehat j - 4\widehat i + \alpha \widehat k} \right) = 0$
Ã¢ÂÂ8 + 12 + 8$\alpha $ = 0
$\alpha  =  - {4 \over 8} =  - {1 \over 2}$

Answer

1/2

Answer

$-$ 1/2

Answer

1

Answer

$-$ 1.

Motion in 2D & Vectors

If a vector 2\widehat i + 3\widehat j + 8\widehat k is perpendicular to the vector 4\widehat j - 4\widehat i + \alpha \widehat k, then the value of \alpha is

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