Plumbing Science

Question 1

What is the unit for resistance?

Answer 1

Ohms

Question 2

What is the power in a domestic property?

Answer 2

230V or 240V

Question 3

What is the unit for power in an appliance?

Answer 3

Watts

Question 4

What is the unit for electromotive force?

Answer 4

Voltage

Question 5

What are the names of the two triangles?

Answer 5

The power triangle and The Ohm’s law triangle

Question 6

What is the unit of electrical energy?

Answer 6

Joules

Question 7

What is the unit for current?

Answer 7

Amperes

Question 8

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

Answer 8

720w or 0.72kW

Question 9

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

Answer 9

240v

Question 10

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

Answer 10

80 ohms

Question 11

What is the fuse size for a domestic appliance which has 1,200 ohms resistance?

Answer 11

0.2 amp

Question 12

What does DC stand for and where does it get it’s power from

Answer 12

Direct current - From batteries

Question 13

What does AC stand for and where does it get it’s power from?

Answer 13

Alternating current - Mains

Question 14

If an appliance had a fuse rated at 13 amp and the resistance was 32 ohms, what would the voltage be?

Answer 14

415v

Question 15

What does Ohms law triangle show the relationship between?

Answer 15

Voltage, Current and Resistance

Question 16

What does the power triangle show the relationship between?

Answer 16

Watts, Amps and Volts

Question 17

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

Answer 17

240v

Question 18

What is the system called containing an earth rod?

Answer 18

TT

Question 19

What is the system called where the neutral wire and the earth wire are connected to the same block?

Answer 19

TNC

Question 20

What is the system called where the earth cable is at a separate point?

Answer 20

TNS

Question 21

What is the role of a miniature circuit breaker (MCB)?

Answer 21

It protects one appliance or circuit and trips out if an overload is detected

Question 22

Where is the miniature circuit breaker found?

Answer 22

In the consumer unit

Question 23

Where is a residual circuit breaker found?

Answer 23

In modern consumer unit

Question 24

What voltage of tools should be used with plug in RCDs?

Answer 24

230v

Question 25

What is the role of an RCD?

Answer 25

Trip out if there is an earth fault

Question 26

Where is the residual circuit breaker with overload (RCBO) located?

Answer 26

Found in the consumer unit

Question 27

What is the purpose of gears in a mechanical engineering system?

Answer 27

Increase or decrease torque

Question 28

Which property measures a materials resistance to being deformed?

Answer 28

Hardness

Question 29

In MES, why is it important to understand the concept of torque?

Answer 29

It measures the force causing rotation

Question 30

Which type of conversion is typically found in an internal combustion engine?

Answer 30

Chemical to mechanical

Question 31

What role do fluids play in a hydraulic system?

Answer 31

They transfer force through pressurised liquid

Question 32

What is the primary difference between force and pressure?

Answer 32

Force is measured in Newtons whereas pressure is measured in pascals

Question 33

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

Answer 33

PVC (Polyvinyl chloride)

Question 34

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

Answer 34

It is highly resistant to rust and corrosion

Question 35

Why is brass often used for fittings in plumbing?

Answer 35

Because of it's strength and it's ability to resist high temperatures

Question 36

In a hydraulic system, pressure is typically measured in which unit?

Answer 36

Pascals

Question 37

In a mechanical engineering system, what does the term 'velocity' refer to?

Answer 37

Speed of an object in a specific direction

Question 38

Which material is used for compression fittings in plumbing?

Answer 38

Brass

Question 39

What is the term for the ability of water to flow between narrow spaces?

Answer 39

Capillarity

Question 40

What is the main component in natural gas?

Answer 40

Methane

Question 41

How many pascals are equivalent to 1 bar of pressure?

Answer 41

100,000 Pa

Question 42

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

Answer 42

Hardness

Question 43

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

Answer 43

Atmospheric pressure

Question 44

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

Answer 44

To prevent sewer gases from entering the building

Question 45

Which unit is used to measure the pressure of water in a plumbing system?

Answer 45

Pascals

Question 46

In a gravity-fed system, which factor has the most direct impact on water pressure at an outlet?

Answer 46

Temperature of water

Question 47

When using a siphon in plumbing, which scientific principle is primarily at work?

Answer 47

Gravity and atmospheric pressure