Dynamics S1 slide 11: Units of unit vectors (ENGR5004) - Revisica

Dynamics S1 slide 11: Units of unit vectorsFrom lectureCurrent specThird1 marks1 min

ENGR5004 Dynamics Session 1, slide 11 (Useful to know, units table)

The "Useful to know" table lists SI units for time (s), position (m), velocity (m/s) and acceleration (m/s $^2$ ), but leaves a "?" for the units of the unit vectors $\mathbf i, \mathbf j, \mathbf k$ (Cartesian), $\mathbf u_n, \mathbf u_t$ (normal-tangential) and $\mathbf u_r, \mathbf u_\theta$ (polar).

What are the units of these unit vectors?

Formulas you may need

Position vector: $\mathbf r = x\mathbf i + y\mathbf j + z\mathbf k$ (learn this)

AmBm/sCNone: they are dimensionlessDrad

Related questions

Dynamics Session 1 Example 1 particle-kinematics, rectilinear-motion, differentiation, harmonic-motion
Dynamics Session 1 Example 2 particle-kinematics, rectilinear-motion, variable-acceleration, separation-of-variables
Dynamics Session 2 Example 1 particle-kinematics, projectile-motion, constant-acceleration, cartesian-coordinates
Dynamics Session 2 Example 2 particle-kinematics, cartesian-coordinates, variable-acceleration, integration
Dynamics Session 3 Worked example 1 particle-kinematics, n-t-coordinates, circular-motion, tangential-acceleration, normal-acceleration
Dynamics Session 3 Worked example 2 particle-kinematics, n-t-coordinates, radius-of-curvature, normal-acceleration
Dynamics Session 4 Worked example 1 particle-kinematics, polar-coordinates, circular-motion
Dynamics Session 4 Worked example 2 particle-kinematics, polar-coordinates, n-t-coordinates, radar-tracking