Machine-translated by Google. Questions are authored in English.
Top

Discussion

The basic dimensions, i.e., mass, length, and time are represented by M, L, and T, respectively. The correct dimension of dynamic viscosity is

  • A.\(MLT^{-2}\)
  • B.\(M^{0}L^{2}T^{-1}\)
  • C.\(ML^{-1}T^{-1}\)
  • D.\(M^{0}L^{-2}T^{2}\)

Answer: C

The dimension of dynamic viscosity is \(ML^{-1}T^{-1}\).

From Newton's law of viscosity, \(\tau = \mu\,du/dy\):

\[ \begin{aligned} [\tau] &= \frac{MLT^{-2}}{L^{2}} = ML^{-1}T^{-2} \\ [du/dy] &= T^{-1} \\ [\mu] &= ML^{-1}T^{-1} \end{aligned} \]

This matches the SI unit Pa.s, which is kg.m-1.s-1. \(MLT^{-2}\) is the dimension of force, and \(L^{2}T^{-1}\) is kinematic viscosity, \(\nu = \mu/\rho\), which has no mass dimension. \(L^{-2}T^{2}\) corresponds to no standard fluid property.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.