Question

The dimensions of the coefficient of viscosity are :

• A. $M{L}^{-1}{T}^{-1}$
• B. $MLT$
• C. $M^{-1}{L}^{-1}{T}^{-1}$
• D. $M^0{L}^0{T}^0$

Answer 1

The correct option is A $M{L}^{-1}{T}^{-1}$

Equation : $F=-\eta Adv/dz$
F=force, A=area,
$\eta$= coefficient of viscosity,
$dv$ is change in velocity when distance change by $dz$

$\left[\eta \right]=\frac{\left[F\right]\left[dz\right]}{\left[A\right]\left[dv\right]}=\frac{\left[ML{T}^{-2}\right]\left[L\right]}{\left[L^2\right]\left[L{T}^{-1}\right]}$

$\left[\eta \right]=\left[M{L}^{-1}{T}^{-1}\right]$