How Can Whales Float?

Today we explored floating and sinking and how a large mammal like a whale can float. We tried floating  raw eggs (whales ) in both tap water and salt water to see if there was any difference

We put the eggs in cups with tap water and salty water .

In tap water the egg sank and in salty water the egg floated.

Why did this happen?

 In our Salt Water Egg experiment, because the egg is denser than tap water, it pushes away water particles so it can make space for itself hence the sinking motion. But in the case of the salt water, since it is heavier than ordinary tap water, it is more capable of holding the egg up – hence the egg floating.  Objects sink when their own density is greater than the liquid’s density.

The same happens to whales. They float because the water they swim in is denser than tap water. The denser the water the easier it is to float.There are other things that help whales to float as well. Can you find out what they are?

We also learned a new word today when the salt we stirred into the water did not all dissolve. We made a saturated solution where the salt could not all be absorbed into the water. Can you think of a way we could make it dissolve?

Have fun and try this experiment at home.