Year 9 Density

Look at this image.  Which object has the LOWEST density in water? How? 

• The Ping Pong Ball because it floats to the top 
• The bolt because it has sunk to the bottom
• The soda cap because it is not just full of air like the Ping Pong ball

Jack has a rock. The rock has a mass of 14g and a volume of 2cm³. What is the density of the rock?

• 7 mL
• 7 g/cm³
• 28 g/cm³
• 1/7 g/cm³

Why do the liquids form different layers?

• They have different densities.  
• They have different masses.  
• They have different volumes.  
• They are different temperatures.  

What units are used to measure mass?

• g
• cm³
• g/cm³
• cm³/g

An object should float in a liquid if it is 

• Denser than the liquid 
• Less dense than the liquid
• Lighter than metal
•  Shaped like a ball 

Why does ice float?

• Liquid water is less dense than solid water.
• Solid water is less dense than liquid water.
• Gaseous water is less dense than solid water.
• Liquid water is less dense than gaseous water.

Put the liquids in order from most dense to least dense?

• 4, 3, 2, 1
• 1, 2, 3, 4
• 3, 4, 2, 1, 
• 4, 3, 1, 2

What is the formula for density?

• density = mass x volume
• density = mass / volume
• density = mass + volume
• density = mass - volume

Helium balloons rise on earth because

• helium is less dense than air
• helium is more dense than air
• helium is cooler than air
• helium is warmer than air

A crayon has a mass of 10g and volume of 5 mL. What is the density?

• 30 g/mL
• 15 g/mL
• 1 g/mL
• 2 g/mL