Re: How come an egg can float in water and salt but not in water and milk?

Archimedes Principle states that when an object is immersed in a fluid, the upwards force is equal to the weight of the water displaced.

So what does that mean?

It means that the denser the liquid in which you immerse the egg, the more force will push upwards on the egg to make it float.

Salt water can be denser than water and milk combined. It depends on how much salt is dissolved in the water.

I suggest you try a little experiment in the kitchen.

Start off with a wide jar filled 3/4 full with water and an egg. You will find that the egg sinks. Take the egg out of the water and add some salt to the water. Stir it up until it dissolves (Adding salt will increase the density of the water). Now add the egg in again and see what happens. Repeat this until you have added enough salt for the egg to float.

[Moderator note: You might also want to try floating an egg in pure milk, or trying to compare the density of milk and water. What weighs more, a quart of water or a quart of milk?]