how do they work? list 5 facts or observations! sketch a diagram
TRANSCRIPT
How do they work?
List 5 facts or observations!
Sketch a diagram
When is it easier to make the divers sink?
• When the bottle has very little air in it.• When the bottle is half-full of air.
A B
Is Water Compressible?Can you change the density of
water by pushing on it?
Is Air Compressible?Can you change the density of
air by pushing on it?
Is Water Compressible?
No. Only air is compressible. The
density of air can change.
Using density, explain why the diver floats.
Water’s density = 1 g/cm3. The diver’s density is less than 1 g/cm3.
1 g/cm3
0.5 g/cm3
Density =
=
= 0.5 g/cm3
Volume
Mass
As compared to water, 0.5 g/cm3 is less dense than water. It floats.
10 g
20 cm3
What changes when you squeeze the bottle? (Don’t say color.)
Volume Changes.
Volume Changes due to increased pressure.
Mass = 10 g Mass = 10 gVolume = 20 cm3 Volume = 5 cm3
Density = 0.5 g/cm3 Density = 2 g/cm3
Density = Mass/Volume
When volume decreases,
Density…
2 g/cm3
Is the mass of the diver changed at all?
No! Mass does not change.
Volume decreases and density increases.
2 g/cm3
1 g/cm3
Using density, explain why the diver sinks.
Water’s density = 1 g/cm3.
The diver’s density is greater than 1 g/cm3.
2 g/cm3
1 g/cm3
Predict
Which diver will sink first?
A B
Predict
Which diver will rise first?
A B
Mass
VolumeDensity =
Review
Review
1. Why does a cube of ice float in water?
Water versus Ice
Water
Question 1
2 g 10 g 20 g
Three cubes have the same volume, but very different densities. Which cube has the greatest density?
Question 2
12 g
Three cylinders have the same volume, but very different densities. Which cylinder will displace the most water when submerged? Or will each cylinder displace the same volume of water?
32 g 8 g
Review
Which is denser?
Both boxes have the same volume.
What is the density of the ship?
Review
Which one is more likely to float in H2O?
Both boxes have the same volume.