Calculate the Density of Paraffin Oil - Physics

Calculate the density of paraffin oil, if glass capillary of diameter 0.25 mm dipped in paraffin oil of surface tension 0.0245 N/m rises to a height of 4 cm. (Angle of contact of paraffin with glass = 28° and acceleration due to gravity = 9.8 m/s2.)

Solution

Given r=0.25/2=0.125mm

=0.12510-3m

T = 0.0245N /m

h=4x10-2m

θ=28º, g=9.8

T=(hrrhog)/(2costheta)

rho=(2Tcostheta)/(hrg)

=(2xx0.0245cos28^@)/(0.125xx10^(-3)xx4xx10^(-2)xx9.8)

=882.9kg/m3

Concept: Capillarity and Capillary Action
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