A circular disc of radius 7//picm is placed horizontally on the surface of water. Find the vertical force required to separate it from the water surface. (Surface tension of water = 0.070N//m)

A circular disc of radius 7//picm is placed horizontally on the surfac

1.	A circular disc of radius 7//picm is placed horizontally on the surface of water. Find the vertical force required to separate it from the water surface. (Surface tension of water = 0.070N//m)
Answer» SOLUTION :The downward FORCE on the circumference of the CIRCULAR disc = `Sxx2piR` Where R is the radius of the circular disc The vertical force required to separate it from the water surface = Downward force `F=Sxx2piR` `S=0.070N//m,R=(7)/(pi)CM=(7)/(pi)xx10^(-2)m` `F=0.070xx2xxpixx(7)/(pi)xx10^(-2)=9.8xx10^(-3)N`