Go To Your Study Dashboard

Get Answers to all your Questions

header-bg

If $\left | A \right |=2$ and $\left | B \right |=4$ , then match the relations in column I with the angle $\theta$ between A and B in column II.

       Column I           Column II

(a) $A.B=0$          (i) $\theta =0$

(b) $A.B=+8$         (ii) $\theta =90^{o}$

(c) $A.B=4$           (iii) $\theta =180^{o}$

(d) $A.B=-8$         (iv) $\theta =60^{o}$

Answers (1)

a) Matches with (ii)

$\left | \vec{A} \right |\left | \vec{B} \right |\; \cos \theta =0$

$\cos \theta =0$

$\theta =90$

b) Matches with (i)

$\left | \vec{A} \right |\left | \vec{B} \right |\; \cos \theta =8$

$2\times4 \cos \theta =8$

$\cos \theta =1$

$\theta =0$

c) Matches with (iv)

$\left | \vec{A} \right |\left | \vec{B} \right |\; \cos \theta =4$

$2\times4 \cos \theta =84$

$\cos \theta =\frac{1}{2}$

$\theta = 60$

d) Matches with (iii)

$\left | \vec{A} \right |\left | \vec{B} \right |\; \cos \theta =-8$

$2\times4 \cos \theta =-8$

$\cos \theta =-1$

$\theta =180$

Posted by

infoexpert23

View full answer

Similar Questions

Latest Question