(a) SURFACE TENSION = \(\frac{\text{force}}{\text{length}}\) FORCE = mass x accel. due to gravity Dimension of force = M.LT\(^{-2}\) Dimension of length = L Dimension of surface area = \(\frac{MLT^{-2}}{L}\) = MT\(^{-2}\) (b) The instruments used for measuring the force of gravity at a place are: (1) Gravimeter, (2) Spring balance, (3) Gravitational accelerometer.