MCQ
A vector $\overrightarrow{ A }$ points vertically upward and $\overrightarrow{ B }$ points towards north. The vector product $\overrightarrow{ A } \times \overrightarrow{ B }$ is
  • A
    null vector
  • along west
  • C
    along east
  • D
    verticaly downward

Answer

Correct option: B.
along west
b
Here $z$-axis is vertically upward means normal to plane of paper as shown in figure.

Thus, $\vec{A}=A \hat{k}$ and $\vec{B}=B \hat{j}$

So, $\overrightarrow{ A } \times \overrightarrow{ B }= A \hat{ k } \times \overrightarrow{ Bj }=- AB \hat{ i }$

Thus, it is along negative $x$-axis means along west.

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