Unit 4 - Fantastic Fluids

Question 0

2. Draw (in your mind) what the particles in a gas, liquid and solid would look like and think of the differences.

Answer 0

|. . | |~~~~~| |………..|
| . .| |. . . | |………..|
| .__.__| |..._.| |………..|
Gas.. Liquid.. Solid..

Question 1

What are the points in the particle theory of matter? (Hint: 5)

Answer 1

1. All matter is made up of very small particles.
2. All particles in a pure substance is the same. Different substances are made of different particles.
3. There is space between particles.
4. Particles are always moving. As they gain energy, they move faster.
5. Particles in a substance are attracted to one another. The strength on the attractive force depends on the type of particle.

Question 2

Know the three properties of matter and define them. (Use: definite shape and volume)

Answer 2

Solid: state of matter where a substance has a definite shape and volume.
Liquid: state of matter where a substance has a volume but no definite shape.
Gas: state of matter where a substance has no definite shape or volume.

Question 3

What are the three states of matter?

Answer 3

Solid, Liquid and Gas.

Question 4

List and describe the changes of state in a substance.

Answer 4

Solid ---> Gas = sublimation
Solid ---> Liquid = melting
Liquid ---> Gas = vaporization
Liquid ---> Solid = freezing
Gas ---> Liquid = condensation
Gas ---> Solid = sublimation

Question 5

Define fluid and give examples.

Answer 5

Fluid: anything that flows, includes liquids and gases. It takes the shape of its container and particles can slide by each other.
Ex) Water, oxygen, honey, milk, carbon dioxide etc.

Question 6

Can you identify fluids from non-fluids?

Answer 6

No matter how small, you can see a solid’s definite shape and volume even if you have to look through a microscope.

Question 7

What is density? Define it in several ways.

Answer 7

Density: How dense something is; the amount of mass in a certain amount of volume.

Question 8

How do we measure the density of a substance?

Answer 8

You can use a scale, beaker and a graduated cylinder. You have to measure the volume and mass of the substance ( d=m/v ).

Question 9

How do we use a triple balance scale?

Answer 9

On a triples balance scale there are three weights: 100g, 10g and 1g. First you place your substance on the scale. Then you move/slide the 100g weight right before the scale tips (indicating that the weight is heavier). The you do the same thing with the 10g weight and then the same thing with the 1g scale. Then you add up the numbers the each weight is on and if you have to you can estimate or round the 1g weight.

Question 10

What is the formula(s) for density?

Answer 10

D=m/v , V=m/d , M=vd

Question 11

What unit is used to describe density?

Answer 11

Grams per cubic-centimetre.

Question 12

Define mass and volume also name the units and tools used for them (tools for to find them).

Answer 12

Mass: the amount of matter in a substance.
Volume: is the measurement of the amount of space occupied of a substance.
Mass is measured in grams (g) or kilograms (kg) and you can use a scale to find it.
Volume is measured in cubic-centimetres (cm3) and you can use displacement to find it.

Question 13

If you have the density and volume … can you calculate the mass of the substance? (List the formula).

Answer 13

Yes. M=vd

Question 14

If you are given the density and mass of a substance… can you measure the volume? (List the formula).

Answer 14

Yes. V=m/d

Question 15

What is buoyancy?

Answer 15

The tendency to rise or float in a fluid. It can be a force on an object.

Question 16

What would it look like for an object, if the buoyant force was stronger then the gravitational force?

Answer 16

~~~~~~~( )~~~~~
⬆️ ⬇️
⬆️
⬆️

Question 17

What would an object look like if the gravitational force is stronger then the buoyant force.

Answer 17

             ⬇️
             ⬇️
    ⬆️     ⬇️
        (  ) ~~~

Question 18

What is the relationship for pressure, area and force?

Answer 18

P=f/a
Pressure: the force acting perpendicular to certain surface area.
Area: the amount of surface; measured in square units such as a squared-centimetre (cm2).
Force: a push or pull, or anything that causes a change in motion on an object.

Question 19

State Archimedes principal and define displacement of water.

Answer 19

The buoyant force acting on an object equals the weight on an object that is displaced.
Displacement: to move something out of the way (e.g. a solid object can displace water out of a container).

Question 20

What’s the difference between a hydraulic system and a pneumatic system? List two advantages and disadvantages about each.

Answer 20

A hydraulic system is pressure of water and a pneumatics system is the pressure for air.
Advantages: (hydraulics) it’s a closed system so you don’t lose any water and the motion can be almost instantly reversed. (pneumatics) the air is dried and free from moisture so it doesn’t create any problems to its internal parts of the system and it can compress the air.
Disadvantages: (hydraulics) you cannot compress it and if you dispose it wrong then the fluid could be an environmental risk. (pneumatics) you lose air when you use it and it’s loudest type of designs that power machines.

Question 21

Define viscosity.

Answer 21

Viscosity: The measure of how fast a fluid will flow; the “thickness” or “thinness” of a fluid.