A small steel needle is carefully floated on water in a b...
A small steel needle is carefully floated on water in a beaker. When a few drops of kerosine are introduced into the water the needle sink.
Which of the following statements correctly explain(s) the observation?
i. there is tension on the water surface
ii. kerosine reduces the density of water so that needle becomes denser than water
iii. kerosine reduces the surface tension of water
i only
ii only
iii only
i and ii
i and iii
Correct answer is E
No explanation has been provided for this answer.
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