TS EAMCET 5-Aug-2021 Shift 1 Question Paper

A metal sheet 4 cm on a side and of negligible thickness is attached to a balance and inserted into container fluid. The balance to which metal sheet is attached read 0.50 N and the contact angle is found to be zero. A small amount of oil is thenspread over the metal sheet. The contact angle now becomes 180° and the balance now reads 0.49 N. The surface tension of the field is