Previous year MCQs

General science UPPSC 1994 GS-I
Question

Why does an iron nail float on mercury while it sinks in water?

Answer & Solution

Answer: (Detailed Solution Below)

Option C: Iron has greater density then water and lesser than, mercury

Detailed Solution:

The correct answer is “Iron has greater density then water and lesser than, mercury”.
An iron nail sinks in water because its density is greater than that of water. However, it floats on mercury because mercury has a much higher density than iron, allowing the nail to float.

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