Question

Which of the following correctly represents a vector in a 3D coordinate system using unit vectors?

Options

• \[R=\sqrt{R_x^2+R_y^2}\]

• \[R=R_x+R_y+R_z\]

• \[R=R_x\hat{i}+R_y\hat{j}\]

• \[R=R_x\hat{i}+R_y\hat{j}+R_z\hat{k}\]

Answer 1

\[R=R_x\hat{i}+R_y\hat{j}+R_z\hat{k}\]

Explanation:

A 3D vector requires three components along the x, y and z axes, represented by unit vectors \[\hat i\], \[\hat j\] and \[\hat k\] respectively.