MCQ
The angle between vectors $(\vec{M} \times \vec{N})$ and $(\bar{N} \times \vec{M})$ is ................
  • A
    $0$
  • B
    $60$
  • C
    $90$
  • $180$

Answer

Correct option: D.
$180$
d
(d)

$\vec{M} \times \vec{N} \neq \vec{N} \times \vec{M}$

$\vec{M} \times \vec{N}$ is from $\vec{M}$ to $\vec{N}$

$\vec{N} \times \vec{M}$ is from $\vec{N}$ to $\vec{M}$

This means the two vectors are in opposite direction.

$\text { So, } \vec{M} \times \vec{N} =\vec{N} \times \vec{M}$

$=180^{\circ}$

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