Question
Physics Question on Surface tension
With the increase of temperature, the surface tension of the liquid
A
may increase or decrease depending on. the density of the liquid
B
remains the same
C
always increases
D
always decreases
Answer
always decreases
Explanation
Solution
Surface tension is the energy that is required to stretch the surface of liquid one incremental amount of area. This requires an input of energy, that is surface tension is positive. It is easier to stretch the surface of a liquid the warmer it gets, because the molecules at the surface are hopping around more, the higher the temperature is. Hence, surface tension always decreases with rise in temperature.