surface tension. physics seminar pdf and ppt

best for seminar and for the project purpose.. All points are contain and not uses for children below 10th and uses for 12 th person and short notes for alternative purpose..

1. SURFACE TENSION
KandulaReena
XllA

2. What is surface tension
Accordingto the definition of surface tension,itthe
phenomenon that occurs when the surface of a liquid is
contact With another phase. It can be a liquid as well . Liquid
tend to acquire the least surface of the liquid behaves like an
elastic sheet

3. Definition of surface tension
Surface tension can be defined as the force acting per unit length
perpendicular on an imaginary line drawn on the liquid surface, tending
to pull the surface apart along the lines
If F is the force acting on the length L of the line AB , then surface tension
is given by, T= F/L

4. What causes surface tension
Intermolecular force’s such as van der waalsforce’s, drawn the
liquid particle together along the surface, the particle are pulled towards
the rest of the liquid surface tension is defined as,
the ratio of the surface force F
to the length L along which the force acts
Mathematically , surface tension can be expressed as follows
. T=F/L

5. Where,
■F is the force per unit length
■L is the length in which force acting
■T is the surface tension of the liquid

6. •Examples of surface tension
■Insect walking on water
■Floating a needle on the surface of the water
■Washing with cold water
■Cleaning of clothes by soap and detergent which lower the
surface tension of the water

7. How to calculate surface tension?
Hereis an example for calculation surface tension bye
using the formula
. Compute the surface tension of a given liquid whose
dragging force is 7N and the length in which the force acts in
2M
Solution :
Given:

8. According to the formula,
T=F/L
. T=7/2
. T=3.5N/M

9. Methods of measurement
Some methods of measurement of surface tension
are given in the points below
■Spinning drop method
■Pendant drop method
■Paddy method
■Ring method
■Plate method

10. ■Drop method
■Stalagmometricmethod
■Bubble pressure method
■Sessile drop method

11. THANK YOU