An air bubble of radius 0.1 cm lies at a depth of 20 cm below the free surface of a liquid of density \(1000kg/{m}^{3}\)…

An air bubble of radius 0.1 cm lies at a depth of 20 cm below the free surface of a liquid of density \(1000kg/{m}^{3}\). If the pressure inside the bubble is \(2100N/{m}^{2}\) greater than the atmospheric pressure, then the surface tension of the liquid in SI unit is (use g\(=10m/{s}^{2}\))