What are the units of a capillary number?

Answer 1

capillary number(Ca)=(viscosity*velocity)/surface tension

viscosity have the unit (kg/(meter*time))

same for velocity(meter/time)

and surface tension ((kg*meter)/(time2*meter))

so= (kg *meter*time*time*meter)/(meter*time*time*kg*meter)

= unitless

dimension={M0 L0 T0}