Question

Dimensions of torque are:

• A. $\left[M^2{L}^2{T}^{-2}\right]$
• B. $\left[M{L}^2{T}^{-2}\right]$
• C. $\left[M{L}^2{T}^{-1}\right]$
• D. $\left[M{L}^0{T}^{-2}\right]$

Answer 1

Answer: (B)

Torque is measured in units of newton-metres. The force applied to a lever, multiplied by its distance from the levers fulcrum is torque.
ie., $\tau =r.F$ or $\tau =N-m$
$\therefore$ $[\tau ]=[M{L}^2{T}^{-2}]$
Torque is the time derivative of angular momentum. Also dimensions of work, kinetic energy and torque are same.