plumbing science

Question 1

what is voltage

Answer 1

The unit for electromotive force

Question 2

What is resistance

Answer 2

The ohm is the unit of resistance which opposes the flow of current

Question 3

what is watts

Answer 3

Watts is the unit of power for an appliance

Question 4

If an appliance needs 3kw in a domestic property what is the fuse size?

Answer 4

3,000 divided by 230=13 amp

Question 4

what is joules

Answer 4

joules is the unit of electrical energy. Today it would be measured in kilo watts an hour.

Question 4

what is the volts in a domestic property

Answer 4

230/240 volts

Question 4

An appliance has a 5 amp fuse and needs 1.2kw of power. What is the voltage required?

Answer 4

1200 divided by 5=240v

Question 5

in a domestic property an appliance has a fuse size of 3 amp.What is the maximum power rating of the appliance?

Answer 5

230 times 3=240w

Question 5

What would be the resistance of a domestic appliance if the fuse size was 3amp?

Answer 5

240 divided by 3=80ohms

Question 5

What is the fuse size for a domestic appliance which has 1200 ohms resistance?

Answer 5

240 divided by 1,200=0.2

Question 5

what does DC stand for?

Answer 5

direct current from battery’s

Question 6

what does AC stand for?

Answer 6

alternating current from mains

Question 7

why is a TNS circuit separate?

Answer 7

A TNS circuit is separate because they all come in at different points

Question 7

Why is a TNC circuit combined?

Answer 7

a TNC circuit is combined because the Earth wire is connected to the neutral wire

Question 7

TT circuit is

Answer 7

different because your earth doesn’t connect to the electrical supply

Question 8

in a hydraulic system, pressure is generally measured in wich unit?

Answer 8

Pascals

Question 9

what is the primary difference between force and pressure?

Answer 9

Force is measured in newtons
pressure is measured in pascals

Question 10

what role do fluids play in a hydraulic system?

Answer 10

they transfer force through pressurised liquid

Question 11

why is stainless steel preferred over other metals for plumbing in areas prone to corrosion?

Answer 11

it is highly resistant to rust and corrosion

Question 12

In a mechanical engineering system what does the term “velocity” refer to?

Answer 12

speed of an object in a specific direction

Question 13

In MES why is it crucial to understand the concept of toque?

Answer 13

it measures the force causing rotation

Question 14

which property measures a materials resistance to being deformed?

Answer 14

Hardness

Question 15

what material is commonly used for modern residential water supply pipes due to its resistance to corrosion and ease of instillation?

Answer 15

PVC (polyvinyl chloride)

Question 16

which plumbing material is proffered for waste, drain and vent piping due to its durability and lightweight properties?

Answer 16

ABS

Question 17

WHAT IS THE sI base unit for length?

Answer 17

metre

Question 18

How many pascals are equivalent to 1 bar of pressure?

Answer 18

100,000 pa

Question 19

which property measures the resistance of a material to deformation or bending?

Answer 19

Hardness

Question 20

What is the specific heat capacity of water?

Answer 20

4.19kj/kg degrees

Question 21

which plastic is used for underground cold water mains?

Answer 21

MDPE

Question 22

What happens to water when it freezes?

Answer 22

its density decreases

Question 23

what is the process of water changing directly from ice to vapor called?

Answer 23

sublimation

Question 24

which type of plastic becomes brittle in freezing temperatures?

Answer 24

Thermoplastics

Question 25

which law explains that pressure exerted on a confined fluid is distributed evenly?

Answer 25

pascals law

Question 26

The resistance of a material to being stretched or pulled

Answer 26

Tensile strength

Question 27

Which law explains that as the speed of a fluid increases, its pressure decreases?

Answer 27

Bernoulli’s Principle

Question 28

Why is it essential to account for thermal expansion in hot water systems?

Answer 28

To prevent damage from expansion of heated pipes

Question 29

How can you convert a temperature from Celsius to kelvin?

Answer 29

add 273.15 to the Celsius temperature

Question 30

Sensible heat is

Answer 30

heat that causes a change in temperature without a phase change

Question 31

what unit is commonly used to measure energy?

Answer 31

Joule

Question 32

which unit is used to measure power, specifically the rate at which energy is transferred?

Answer 32

Watt

Question 33

Which scientific principle is used in plumbing to prevent backflow in water systems?

Answer 33

Atmospheric Pressure

Question 34

What is the main factor that affects water pressure in a plumbing system?

Answer 34

Height and gravity

Question 35

in a closed plumbing system, increasing the temperature of the water typically causes:

Answer 35

Increase in water pressure

Question 36

Why are U-bends or P-traps used in plumbing systems?

Answer 36

To prevent sewer gases from entering buildings

Question 37

best describes the function of a non-return valve in a plumbing system?

Answer 37

Allows water to flow in one direction only

Question 38

In a heating system, why is an expansion vessel important?

Answer 38

It compensates for the expansion of water when heated