Question

a capillary tube of radius 5×10^-4 is dipped into a beaker of Mercury the Mercury meniscus inside the capillary tube is 10.3 mm below the Mercury level in the beaker determine the angle of contact between Mercury and the glass

Answer 1

Answer:

Given,

Radius of capillary tube=0.5mm

=0.5×10

−3

m

Level inside tube=0.8cm

=0.8×10

−2

m

Angle of contract, θ=120

o

Mass density of mercury,

ρ=13.6×10

3

kg/m

2

Acceleration due to gravity, g=10m/s

2

h=

rρg

2Tcosθ

T=

2cosθ

hrρg

=

2×cos120

0.8×10

−2

×0.5×10

−3

×13.6×10

3

×10

=

2×

2

1

0.8×10

−2

×0.5×10

−3

×13.6×10

3

×10

=0.8×0.5×13.6×10

−1

=0.544N/m.