Question

For \[\vec{a}=a_1\hat{i}+a_2\hat{j}+a_3\hat{k}\], which quantities are called the components of \[\vec{a}\]?

Options

• \[a_1,a_2,a_3\]

• \[\sqrt{a_1^2+a_2^2+a_3^2}\]

• \[a_1+a_2+a_3\]

• \[\hat{i},\hat{j},\hat{k}\]

Answer 1

In \[\vec{a}=a_1\hat{i}+a_2\hat{j}+a_3\hat{k}\], the numbers multiplying the unit vectors are the components. Hence \[a_1,a_2,a_3\] are the components of \[\vec{a}\].