Two soap bubbles of radii a and b combine to form a single bubble of radius 3) If P is the external pressure, then S.T. of the soap solutionis
- $\frac{P(c^3 +a^3+b^3)}{4(a^2+b^2+c^2)}$
- $\frac{P(c^3 -a^3-b^3)}{4(a^2+b^2-c^2)}$
- $Pc^3-4a^2-4b^2$
- $Pc^3-2a^2-3b^2$
The Correct Option is B
Solution and Explanation
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Concepts Used:
Surface Tension
The amount of energy required to increase the liquid's surface area by one unit area is known as surface tension. In other words, it is a property of the liquid surface to resist force.
Surface tension is defined as,
The ratio of the surface force F to the length L along which the force acts.
Mathematically, the surface tension formula can be expressed as follows:
T=F/L
Where,
- F is the force per unit length
- L is the length in which force act
- T is the surface tension of the liquid
Read More: Detergents and Surface Tension
Factors affecting surface tension:
- Impurities: The surface tension decreases with the addition of impurities.
- Surfactants: Adding surfactants in liquids lowers the tension of water making it interrupt aside or get susceptible.
- Temperature: The surface tension of a liquid reduces as the temperature rises.
The Unit of Surface Tension:
The SI unit of Surface Tension is Newton per Meter or N/m.