States of Matter
In which state of matter are particles held tightly together, strongly attracted to each other, and very dense?
Solid
Luisa throws a stone into the lake. It sinks to the bottom. Is the stone positively or negatively buoyant?
Negatively buoyant.
What is viscosity?
Viscosity is a measure of a fluid’s resistance to flow.
What is the main difference between a hydraulic and pneumatic system?
A hydraulic system involves compressed liquid. A pneumatic system involves compressed gas.
Hydroelectric dams and wind turbines use the flow of liquids and gases to generate...
Power/Electricity/Energy
In which state of matter are particles barely attracted to each other, move very rapidly in all directions, and not very dense?
Gas
If a rubber ducky is positively buoyant in water, what does that tell us about its density?
The ducky is less dense than the water.
True or False: Cold ketchup will flow faster than room temperature ketchup.
False. It will flow slower because we know that temperature affects viscosity.
Pneumatic system because they use oxygen (gas).
Why might some people say wind turbines are bad for the environment?
They are loud structures that create noise pollution and have blades that might harm flying animals.
In which state of matter are particles fairly attracted to each other, but are less densely packed than solids?
Liquid
If an object has a large mass but a small volume, the mass is packed in tightly. Does this mean the object will have high or low density?
High density.
Spoiled, chunky milk flows slower than fresh milk. Why is that?
This is because spoiled milk has suspended particles (chunks) in it, which makes it more viscous.
True or False: It takes less effort to compress a gas than a liquid.
True
True or False: Hydroelectric dams do not change the flow of water.
False - they do!
True or False: When particles are heated, they move faster.
True
In which state of matter are particles the least dense?
Gas
Use your understanding of viscosity and temperature to explain the saying, "He moves slower than molasses in January".
The saying describes someone moving extremely slow. Molasses is already very viscous, and it becomes even more viscous in cold temperatures.
What are valves used for?
Valves are used to regulate the flow of fluids.
Why might some people say that hydraulic systems lead to unemployment?
Machines can replace human workers.
Why are liquids and gases considered to be fluids, but solids are not?
Oil floats on top of water. What does this tell us about the oil's density and buoyancy?
Oil is less dense than water, so it is positively buoyant.
Honey because it flows slower when poured.
What does Pascal's law state?
Pascal’s law states that if pressure is exerted on a fluid, it will be evenly distributed throughout the fluid.
Why might people say that oil pipelines pose a threat to the environment?
If they leak or burst, the oil can seep into the environment. This can harm animal habitats and contaminate drinking water.