1. 4.1 – A Close-Up Look at Fluid Flow
Chapter 4 - Fluids
4.1 – A Close-Up Look at Fluid Flow

2. A Close-Up Look at Fluid Flow
Fluids are substances that _______
Both _______ and __________ are fluids
Fluids flow because some sort of force is exerted on them
A force is a _______ or ________ that causes changes in movement

3. Common Forces __________ is one of the most common forces
It helps water run downhill and ketchup pour from a bottle
Fluids can also be made to move by a ___________ force exerted by a pump
Water flowing through a pipe is ____________ down by the force of friction between the water and the walls of the pipe

4. Fluid Flow
Fluid flow involves both the _____________ of a fluid and the movement of an object through a fluid
How __________ a fluid flows in a given amount of time is called its flow rate

5. Systems that involve ____________, such as moving fluids, are said to be ___________
Air or gas moving around solid objects is referred to as __________
The motion of liquids around solid objects is referred to as ______________

6. The Kinetic Molecular Theory
All matter can exist in __________ states and can change from one state to another
Solid, liquid, or gas
The___________molecular theory provides a model to help us understand how matter can change from one state to another

7. The Kinetic Molecular Theory
The kinetic molecular theory states that
All matter is composed of molecules or other types of particles
Particles are in constant motion
There are forces of attraction among particles
The change from one state to another is caused by either an increase or a decrease in the___________of the substance

8. Changes of State

9. Solid
In ________ water (ice), the particles have a low energy level and are close together
The force of attraction is high and holds the particles together
The particles are still in motion, but they ________ around a fixed position
Solids have a definite shape and volume

10. Liquid
Liquids have a definite ____________ but do not have a definite shape
Liquids take the shape of the container they are in

11. Gases Gases do not have a definite shape or volume
The particles of a gas spread out to fill a container of any size or shape

12. Melting
As heat energy is added to ice, the motion of the particles increases and the forces of attraction among them are not as strong
The particles are now able to move around more easily and can slide past each other
The solid (ice) becomes a liquid (water)

13. Evaporation
If you continue to add heat energy to the liquid, the particles move even faster and farther apart
The forces of attraction among the particles becomes smaller and smaller
The forces of attraction are smallest on the particles near the surface of the liquid
Once enough heat energy is added, individual particles break away from the surface of the liquid and become a gas

14. Condensation
As heat energy is removed from a gas, the particles start to slow down
The gas becomes a liquid
This process of changing matter from a gas to a liquid is called condensation

15. Solidification
Removing even more heat energy can cause a liquid to change to a solid
This process is called solidification (aka: freezing)

16. Sublimation and Deposition
Water can also change directly from a solid to a gas without going through the liquid state
This is called sublimation
Water can also change directly from a gas to a solid
This is called deposition