Flotation

Question 0

Solid and liquids

Answer 0

A solid will float in a liquid if the solid is less dense than the liquid.

A liquid will float on top of another liquid if the liquid on top is less dense.

Question 1

Flotation

Answer 1

We observe many examples of floating objects in our everyday lives. Boats float in the sea, twigs float in rivers and we know that icebergs are huge floating blocks of ice.
Why do some objects float and other objects sink? The answer to this question is to think about the density of the objects.

Question 2

What floats

Answer 2

Cork will float in paraffin oil
Ice will sink in paraffin oil
Ice will float in water
Paraffin oil will float on top of water
Gold will sink in water.

Note: Did you ever wonder why a ship, which is made of a metal, is able to float in water? If the metal is denser than the water then the ship should sink.
However, the ship is hollow and the inside of the ship is filled with air. The average density of the ship and the air is less than the density of the water. The ship is therefore able to float.

Question 3

How to get the density?

Answer 3

Density =
Mass
_____

Volume

The units for density are either g cm–3 or kg m–3
For numerical questions remember.

A solid will float in a liquid if the solid is less dense than the liquid.
A liquid will float on top of another liquid if the liquid on top is less dense.