Two narrow capillary tubes A and B are of lengths ( and 111 and of same radius r. The rate of flow of water through the tube A under a constant pressure head P is 3 $ \sqrt{\text{49}0}\text{ m}/\text{s} $ . If A and B are connected in series and the same pressure difference P is maintained between the ends of the composite tube, then the rate of flow of water is :
- $ \sqrt{\text{4}\text{.9}}\text{ m}/\text{s} $
- $ 8\sqrt{3} $
- $ 2\sqrt{3}cm $
- none of these
The Correct Option is C
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.