Fluids - 7.2 Grade 8 Flashcards
What is matter?
Matter: Anything that has mass and volume.
What is mass?
Mass: A measure of how much matter there is in a substance.
What is volume?
Volume: A measure of how much space a substance takes up.
What is thermal expansion?
Thermal Expansion: an increase in the volume of a substance in response to an increase in its temperature.
What is the particle theory of matter? And what are the six main points?
The particle theory of matter is a simple way of describing matter and its behavior.
The six main points:
All matter is made up of tiny particles.
All particles are in constant motion.
All particles of one substance are identical.
Temperature affects the speed at which particles move.
In liquids and solids, the particles are close together and have forces of attraction between them.
In a gas, there are spaces between the particles.
Why can liquids flow? Give an example.
They can flow because particles in a liquid can overcome some of their attraction to each other and slide past each other. Ex. water takes a different shape in a vase compared to in a bowl.
Why can gases flow? Give an example.
They can flow because gas particles move so quickly and are so far apart that they overcome almost all of their attraction to each other. Ex. When you spray some air freshener in one part of a room, soon you will be able to smell it in other parts of the room.
Explain what happens to the particles of a solid, liquid, or gas when the temperature both increases and decreases? What happens as a result (regarding the substance)? Give an example.
When the temperature of a solid, liquid, or gas increases, particles move faster and farther apart. As a result, the
substance expands.
When the temperature of a solid, liquid, or gas decreases, its particles move more slowly and closer together. As a result the substance shrinks or contracts.
Ex. A thermometer - It shows the temperature by the expansion or contraction of a liquid in a narrow tube. When the temperature rises, the particles in the tube move farther apart as their motion increases. When the temperature drops, the particles in the tube move closer together and the level of liquid falls.
What are the 2 characteristics of all fluids?
*talk about volume of liquids and gases.
Two characteristics of all fluids:
- All fluids can move or flow
- All fluids do not have a definite shape. (liquids have a fixed volume, gases do not have a fixed volume)
What is drag?
Drag: opposing force or resistance posed by the air towards the moving or speeding object.
What is laminar flow?
- how do fluids move in laminar flow (way and speed)?
- What does laminar flow of air reduce in the case of a moving vehicle?
- Give 1 example of laminar flow.
Laminar flow is a smooth and regular flow of fluids
Fluids move in orderly lines or smooth pathways
Fluids move more quickly
Laminar flow of air reduces the drag in the case of a moving vehicle and makes them more efficient.
Ex. flow of blood in the vessels of a healthy person
What is turbulent flow? Give an example.
Turbulent flow is the choppy and irregular flow of fluids. Ex. The flow of the river down a slope is called turbulent flow of the river.
What creates more laminar flow?
The streamlined shape of objects creates more laminar flow.
