Question

Exercise 1.42 Part A Given two vectors A = 4.801 + 7.00 j and B = 5.101-2.60 j , find the scalar product of the two vectors A and B Submit Request Answer Part B Find the angle between these two vectors. 0图 SubmitRec Request Answer Provide Feedback

Answer 1

a)

$\overrightarrow{A}.\overrightarrow{B}=(4.8\widehat{i}+7\widehat{j}).(5.1\widehat{i}-2.6\widehat{j})=4.8\times 5.1-7\times 2.6=6.28$

b)

Angle between the two vectors A and B is

$\theta =Cos^{-1}\left ( \frac{\overrightarrow{A}.\overrightarrow{B}}{\left | \overrightarrow{A} \right |.\left | \overrightarrow{B} \right |} \right )=Cos^{-1}\left ( \frac{6.28}{\sqrt{4.8^{2}+7^{2}}\times \sqrt{5.1^{2}+(-2.6)^{2}}} \right )=82.57^{o}$