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3.1 vectors — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysics3.1 vectors1 Mark
MCQ
A vector $\vec{A}$ points towards North and vector $\vec{B}$ points upwards then $\vec{A} \times \vec{B}$ points towards ...........
  • ✓
    East
  • B
    West
  • C
    North
  • D
    South
✓

Answer

Correct option: A.
East
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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