A capillary tube of diameter 4 mm is dipped into a liquid of specific gravity 0.6. The liquid rises in the tube by 20 mm, making an angle of contact of 0° with the tube. Determine the surface tension of the liquid in contact with air and the glass tube.
1
0.12 N/m
2
0.5 N/m
3
1 N/m
4
0.08 N/m