Verifying Dimensionality of Fall Velocity Equation

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SUMMARY

The fall velocity equation for a particle in a viscous medium is defined as Vt = gd^2(Pp - Pm) / 18 u. This equation is dimensionally homogeneous, as both sides equate to m/s. The variables include g (acceleration due to gravity), d (particle diameter), Pp (density of the particle), Pm (density of the medium), and u (viscosity of the medium). A detailed dimensional analysis confirms that the units cancel appropriately, leading to the correct dimensional consistency.

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jase03
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The equation for the fall velocity (terminal velocity) of a particle of a material in a viscous medium has been derived from theory as:

Vt = gd^2(Pp - Pm) / 18 u

Where: Vt is the terminal velocity in m/s; g is the acceleration due to gravity; d is particle diameter in m; Pp and Pm are the densities of the particle and the medium (respectively) in kg/m^3; u is the viscocity of the medium in kg/m/s (kg.m^-1.s^-1)

Demonstrate if this equation is dimensionally homogeneous or not. Show your working.


Could someone show me how you work this out with the cancelling of units.

My final answer I'm getting - m/s = m/s x m

I don't think I'm correct.


Regards
Jason
 
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If you show all your steps in the working one can point out where the mistake is.
 

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