MCQ
A vector $\vec{A}$ points towards North and vector $\vec{B}$ points upwards then $\vec{A} \times \vec{B}$ points towards ...........
- ✓East
- BWest
- CNorth
- DSouth
✓
Answer
Correct option: A.
East
a
(a)
(a)
Here $z$-axis is vertically upward means normal to plane of paper as shown in figure.
Thus, $\overrightarrow{ A }= A \hat{ k }$ and $\overrightarrow{ B }= B \hat{ j }$
So, $\overrightarrow{ A } \times \overrightarrow{ B }= A \hat{ k } \times B \hat{ j }=- AB \hat{ i }$
Thus, it is along negative $x$-axis means along west.
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