Fluid Mechanics

JEE Main level, single correct, medium

174 of 192

Question 174 of 192

Given below are two statements :
Statement (I) : Viscosity of gases is greater than that of liquids.

Statement (II) : Surface tension of a liquid decreases due to the presence of insoluble impurities.

In the light of the above statements, choose the most appropriate answer from the options given below :

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Answer: (B) Statement I is incorrect but Statement II is correct

Viscosity is a measure of a fluid's resistance to flow, and gases typically have lower molecular interactions and are less dense than liquids, resulting in lower viscosity.
The presence of insoluble impurities in a liquid can decrease its surface tension. Surface tension is related to the cohesive forces between molecules at the surface of a liquid. Insoluble impurities can disrupt these cohesive forces, leading to a decrease in surface tension.

Hence, this is the correct option.

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