Which one of the following statements is ‘NOT’ true about the angle of contact of a liquid?
Which one of the following statements is ‘NOT’ true about the angle of contact of a liquid?
- Any increase in the temperature of the liquid does not decrease its angle of contact.
- Angle of contact depends upon the nature of liquid and solid in contact
- If an impurity is added in the liquid then it’s angle of contact changes.
- At a given temperature, the angle of contact is constant for a solid-liquid surface.
The Correct Option is D
Solution and Explanation
The angle of contact is not necessarily constant for a solid-liquid surface at a given temperature. It can vary depending on various factors such as the nature of the liquid and solid in contact, the presence of impurities, and the surface tension of the liquid.
So, the correct answer is (D) At a given temperature, the angle of contact is constant for a solid-liquid surface.
Top Questions on mechanical properties of fluid
Water flows through a horizontal tube as shown in the figure. The difference in height between the water columns in vertical tubes is 5 cm and the area of cross-sections at A and B are 6 cm\(^2\) and 3 cm\(^2\) respectively. The rate of flow will be ______ cm\(^3\)/s. (take g = 10 m/s\(^2\)).
- JEE Main - 2026
- Physics
- mechanical properties of fluid
- Given below are two statements:
Statement I: Pressure of a fluid is exerted only on a solid surface in contact as the fluid-pressure does not exist everywhere in a still fluid.
Statement II: Excess potential energy of the molecules on the surface of a liquid, when compared to interior, results in surface tension.
In the light of the above statements, choose the correct answer from the options given below- JEE Main - 2026
- Physics
- mechanical properties of fluid
- A water tank is open at the top and has a hole of area \( 10^{-4} \, \text{m}^2 \) at the bottom. The height of the water column is 5 m. What is the speed of the water flowing out of the hole? (Take \( g = 10 \, \text{m/s}^2 \))
- MHT CET - 2025
- Physics
- mechanical properties of fluid
- Water is being poured at the rate of 36 m$^3$/min into a cylindrical vessel whose circular base is of radius 3 meters. Then the water level in the cylinder increases at the rate of:
- MHT CET - 2025
- Physics
- mechanical properties of fluid
- A fluid flows through a pipe with a varying cross-sectional area. If the velocity of the fluid is \( v_1 = 4 \, \text{m/s} \) at a point where the cross-sectional area is \( A_1 = 2 \, \text{m}^2 \), and the velocity at another point where the cross-sectional area is \( A_2 = 1 \, \text{m}^2 \) is \( v_2 \), what is the velocity \( v_2 \)?
- MHT CET - 2025
- Physics
- mechanical properties of fluid
Questions Asked in MHT CET exam
Which part of root absorb mineral?
- MHT CET - 2025
- The Root
- A body of mass 2 kg is moving in a circular path of radius 3 m with a constant speed of 6 m/s. What is the centripetal force acting on the body?
- MHT CET - 2025
- Centripetal forces
- A 200 g sample of water at 80°C is mixed with 100 g of water at 20°C. Assuming no heat loss to the surroundings, what is the final temperature of the mixture?
- MHT CET - 2025
- thermal properties of matter
- Given the equation: \[ 81 \sin^2 x + 81 \cos^2 x = 30 \] Find the value of \( x \).
- MHT CET - 2025
- Trigonometric Identities
- A body of mass 10 kg is at a height of 5 m above the surface of the Earth. What is the gravitational potential energy of the body? (Take \( g = 10 \, \text{m/s}^2 \))
- MHT CET - 2025
- Gravitational Potential Energy
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.