Gases

Question 1

What is the difference between gases and liquids?

Answer 1

Gases can be compressed while liquids are nearly incompressible.

A liquid has a fixed volumes while gases have a unlimited volume and take up as much volume as the surrounding pressure will allow

Question 2

What did Robert Boyle discover?

Answer 2

studied the relationship between pressure and the volume of a gas at a constant temperature

Formulated the following law:
As the temperature of a gas is increased, the molecules of the gas become more active. This causes more space between the molecules and thus an increase in volume of the original gas

volume 1 / volume 2 = pressure 2 / pressure 1

or v1 = V2 x P2 / P1

Question 3

Charles’ Law

Answer 3

discovered the relationship between the volume of a gas and the temperature of a gas at a constant pressure

volume 1 / volume 2 = temperature 1 / temperature 2

Question 4

Ideal Gas Law

Answer 4

Boyle’s Law and Charles’ Law can be combined to form the ideal gas law

correct at normal conditions, but not at extreme temperatures and pressures

pressure 1 x volume 1 / temperature 1 = pressure 2 x volume 2 / temperature 2

Question 5

When is heat generated?

Answer 5

When gas is compressed because of the friction generated between the molecules

Question 6

As the temperature of a gas rises..

Answer 6

the pressure increases

Question 7

As the pressure of gas decreases..

Answer 7

the temperature drops

Question 8

How do you find the specific gravity of a gas?

Answer 8

found by comparing the weight of an equal volume of the gas with that of air

Question 9

Fuels that are heavier than air will..

Answer 9

migrate to the lowest point and settle there.

Question 10

Specific gravity

Answer 10

weight of a volume of gas / weight of an equal volume of air

Question 11

barometer

Answer 11

an instrument used to measure atmospheric pressure

Question 12

Most common type of barometer is the..

Answer 12

mercury barometer

Question 13

Bernoulli’s Gas Principle

Answer 13

studied the movement of objects through air

the difference between high pressure and low pressure results in unbalanced forces as air moves across the body

Question 14

When is lift created?

Answer 14

when an airfoil shape was placed in wind

the air moving over the top of the airfoil has to travel a greater distance to reach the trailing edge of the airfoil

the air over the top of the wing increases in speed and causes a low pressure area of the top of the wing

when the airstream makes contact with the bottom of the airfoil, the air is deflected downward

creates high pressure area under the wing and forces the wing upward

Question 15

pneumatic force

Answer 15

force that varies with the area of the cylinder and the air pressure which is supplied to the cylinder

Question 16

pneumatic pump

Answer 16

a device used to compress air for pneumatic applications

Question 17

pneumatic valve

Answer 17

a valve that controls the direction of the compressed air

Question 18

pneumatic with levers

Answer 18

the distance a pneumatic ram moves an object can be increased or decreased with the use of a lever

Question 19

What are pneumatics used for?

Answer 19

compressed air that can be used to operate a large group of tools and machines

used in manufacturing for calming, drilling and positioning materials for assembly

robots are control with pneumatics

air is available in unlimited quantities–can be compressed readily, stored in reservoirs, and converted through hoses and pipelines

Question 20

Pros & Cons of pneumatic machines

Answer 20

Pros:

Compact, light and simple to manufacture