In which of the following is surface tension important?
- the floating of a ship in water
-
the floating of a dry needle in water
- the floating of a baloon in air
- the diffusion of sugar solution across a membrane
The correct answer is: B
Explanation
A carefully placed small needle can be made to float on the surface of water even though it is several times as dense as water. If the surface is agitated to break up the surface tension, then needle will quickly sink.