Density and Buoyancy Concepts

The video explores why some objects float while others sink, introducing the concept of density. It explains density in liquids using oil and water, and provides a formula for calculating density with an example. The video compares the densities of different materials and illustrates how density is observed in daily life, such as in hot air balloons and icebergs.

Why do some objects float while others sink?

• Because of their color

• Due to their density

• Because of their shape

• Due to their temperature

What is the formula for calculating density?

• Density = Volume x Mass

• Density = Volume / Mass

• Density = Mass / Volume

• Density = Mass x Volume

If a cork has a mass of 0.36 grams and a volume of 1.5 cm³, what is its density?

• 0.36 g/cm³

• 0.54 g/cm³

• 1.5 g/cm³

• 0.24 g/cm³

Which material is the most dense in a measuring cylinder?

• Cork

• Mercury

• Copper

• Water

Why does water float on mercury?

• Because water is denser than mercury

• Because mercury is denser than water

• Because water is heavier than mercury

• Because they are both equally dense

Which of the following is less dense than water?

• Copper

• Mercury

• Cork

• Petrol

What is the density of petrol compared to water?

• Petrol is less dense than water

• Petrol is denser than water

• Petrol is heavier than water

• Petrol and water have the same density

How does density affect the floating of a hot air balloon?

• The balloon sinks because it is denser than air

• The balloon floats because it is less dense than air

• The balloon floats because it is denser than air

• The balloon sinks because it is less dense than air

Why does timber float on a river?

• Because it is lighter than water

• Because it is heavier than water

• Because it is less dense than water

• Because it is denser than water

What allows icebergs to float on the surface of water?

• Icebergs are denser than water

• Icebergs are less dense than water

• Icebergs are heavier than water

• Icebergs are lighter than water