Worksheets[MOCK EXAM] Scientific Principles - Mock Exam
Total questions: 75
Worksheet time: 42mins
Which pipe, measuring 6m in length, will offer the greatest resistance to the flow of water?
15mm pipe with four elbows
15mm pipe with four machine bends
22mm pipe, reduces down to 15mm halfway along its length
15mm pipe with two machine bends and two elbows
Conduction occurs by
Heat travelling in a straight line through the air
Heat travelling through or along a solid material
Heat travelling via a chemical reaction
Heat travelling via the motion of a fluid
What is this symbol for?
DC electricity
System circulator
Electrical resistance
AC electricity
Which of the following will cause siphonage to occur?
Suction at point C
Increase in pressure at point B
Suction at point A
Atmospheric pressure in the tube
What is the freezing point of water at sea level?
100°C
75°C
25°C
0°C
Which of the following materials is the best conductor of heat?
Lead
Low carbon steel
Copper
Cast iron
What would the fuse size be for a domestic appliance that has a power rating of 3kW?
13 amp
10 amp
5 amp
3 amp
Which of the following values reflects the pH value for pure water?
1
4
7
11
The limescale build-up in systems is caused by?
Soft water
Acidic water
Temporary hard water
Permanently hard water
This form of corrosion is generally caused by?
Flux left in the tube after flushing out
The inhibitor in the system being too strong
Position of the electrolytic series table
Bad manufacture
A change of state may occur when water is heated to (At sea level)?
25°C
50°C
75°C
100°C
The SI unit for measuring electrical current is?
Watt
Ampere
Joule
Ohm
Specific heat capacity is measured in?
N/m²
°C or °K
KJ/Kg/°C
Amperes
What has a sinusoidal wave form?
DC electricity
AC electricity
Convection heat transfer
Conductive heat transfer
If a customer painted their central heating pipework, what would that protect it from?
Pitting
Electrolytic corrosion
Atmospheric corrosion
UV corrosion
On an incoming mains, which of the following would have the lowest pressure?
The cold water tap at the kitchen sink
The float-operated valve to the CWSC in the loft
The first floor basin cold tap
The downstairs WC float-operated valve
What is the relative density of water?
9.81
7
1
25
What is Zinc classified as?
Ferrous
Alloy
Non-ferrous
Thermoplastic
Dezincification occurs in which of the following materials?
Iron
Brass
Nickel
Copper
What is the unit of electrical resistance?
Ampere
Volt
Ohm
Power
What is the unit of electrical power?
Ampere
Volt
Ohm
Watt
Polybutylene, polyethylene and polypropylene are which kind of plastic?
Thermoplastics
Thermosetting
Epoxies
Polyester
If a substance of less than 1.0 relative density what will happen when it is put into water?
It will sink
It will freeze
It will dissolve
It will float
What does this scale stand for?
PH Value
HP Value
ANA Value
Temperature scale
What is being shown in the image?
Gravity circulation
Forced circulation
Parasitic circulation
Boiler circulation
What type of heat is A?
Convection
Radiation
Moving
Warm
What does the following formula mean?
Velocity ratio
Volume rate
Variable speed rate
Volume ratio
Density is a measurement of?
Mass × volume
Weight × volume
Weight ÷ volume
Mass ÷ volume
What is the mass of 1 m³ of water at 4°C?
100 kg
1000 kg
350 kg
9.8 kg
Lead is a very ‘malleable’ metal. What does malleable mean?
It has a high melting point
It is easily worked without fracture
It can be drawn out to form wire without fracture
It resists being pulled apart
Which metal is used to galvanise low carbon steel?
Zinc
Chrome
Nickel
Boron
Which type of plastic is used most frequently in the manufacture of plumbing materials?
Thermoplastic
Thermosetting
Technoplastic
Technosetting
What is bronze made from?
Copper and tin
Copper and zinc
Copper and lead
Copper and magnesium
What is the SI unit for measuring temperature?
Kelvin
Celsius
Fahrenheit
Centigrade
Capillary action is increased if?
Materials are closer together
Materials are further apart
Water is acidic
Water is alkaline
What does siphonage depend on?
Atmospheric pressure
Water temperature
Capillary action
The height of the cistern
Water reaches its maximum density at a temperature of?
0°C
4°C
20°C
60°C
If 1m³ of lead has a mass of 11,400 kg, on this principle what is its relative density?
11.4
9.8
7.2
22.4
The pH scale is used to measure?
Atmospheric pressure
Specific gravity
Acidity and alkalinity
Heat loss
Electrolytic corrosion can be reduced by using a sacrificial?
Electrolyte
Cathode
Inhibitor
Anode
Kelvin is the SI unit for measuring?
Linear expansion
Temperature
Pressure
Force
An example of the effect of adhesion and cohesion can be seen in?
Siphonage action
Frictional resistance
Stratification
Capillary attraction
Capillary attraction can take place on roof weatherings if?
The weathering materials are lapped closely together
The weathering materials are kept apart
The water has a high pH value
The weatherings are of dissimilar materials
Which of the following would have the greatest frictional resistance on the flow of water?
3 m 22 mm copper pipe one bend
3 m 22 mm copper pipe
3 m 20 mm low carbon steel one elbow
3 m 20 mm low carbon steel
Which of the following gases are likely to explode if 13% is mixed with air?
Butane
Nitrogen
Propane
Methane
What does the abbreviation BSI stand for?
Best Spoke Institution
British Standard Institution
Building Standard Institution
British Specification Institution
Low Carbon Steel (LCS) is an alloy made from carbon and?
Zinc
Chrome
Iron
Boron
Load is expressed in terms of force per unit area and is measured in?
Mohs
Watts
Metres
Newtons
What installation pipe material is now generally prohibited for use?
Stainless steel
Copper
Galvanised iron
Lead
At what temperature does water reach its maximum density?
0°C
2°C
4°C
8°C
What happens to the molecules when a substance changes state from a liquid to a gas?
They move further apart
They begin to vibrate
They move closer together
They fuse together
What plumbing system by-product is most directly linked to hard water?
Carbon dioxide
Hydrogen
Ferrous oxide
Limescale
Water from an area which has a limestone and chalk strata is most likely to be?
Alkaline
Acidic
Cloudy
Neutral
In which combination of metals would electrolytic corrosion be most pronounced?
Copper and lead
Iron and zinc
Copper and aluminium
Aluminium and magnesium
What does ferrous mean when classifying metals?
Magnetic, Contains Iron
Non-Magnetic, Does NOT contain Iron
Flux needs applying to the metal to stop corrosion
Poisonous to install
What does MDPE stand for?
Medium Density Polyethylene
Multi-Diameter Polyethylene Elbow
Moulded Durable Plumbing Elastomer
Modified Density Polyethylene Element
Calculate the amount of heat required to raise 502 litres of water in the cylinder from 15oC to 65oC.
104,918KJ
100.002KJ
4075.5KJ
25,100KJ
Calculate the power required from the immersion heater if:
You have a vessel which contains 150 L of water and needs heating by 50ºC in one hour.
8.7KW
7500KW
31,350KW
10KW
Specific Heat Capacity is?
The amount of heat required to raise the temperature of 1 kg of a substance by 1°C.
The total heat energy a material can store at any temperature.
The rate at which heat is transferred through a material per unit area.
The amount of energy required to convert 1 kg of a substance from solid to liquid.
What is sensible heat?
Heat that causes a change in temperature of a substance without a change in state
Heat that causes a change in temperature of a substance with a change in state
Heat absorbed or released during a change in state at constant temperature.
Heat that is transferred through radiation only.
What is latent heat?
Heat that causes a change in temperature of a substance without a change in state
Heat that causes a change in temperature of a substance with a change in state
Heat absorbed or released during a change in state at constant temperature.
Heat that is transferred through radiation only.
Complete the power triangle relationship between Watts - Amps - Volts
Complete the Ohms Law triangle relationship between Voltage - Current - Resistance
A water pump in a plumbing system operates with a resistance of 8Ω and is connected to a 24V power supply. What is the current flowing through the pump?
3 Amps
12 Amps
0.33 Amps
192 Amps
An electric water heater in a plumbing system operates at 240V and draws 8A of current. What is the power consumption of the heater?
1920 Watts
280 Watts
29 Watts
960 Watts
How do you calculate the volume of a cylindrical water tank in a plumbing system?
π × radius² × height
2 × π × radius × height
π × radius × height x diameter
π × radius² × diameter
What is the formula to calculate specific heat capacity ?
quantity of water (litres) × 4.18 × ΔT
quantity of water (litres) × 4.18 × T
4.18 × ΔT
quantity of water (litres) × ΔT
In a plumbing system, a plumber uses a lever to lift a heavy pipe. If the load is 200N and the load arm is 4 meters long, and the effort arm is 2 meters long, how much effort (force) is required?
50N
100N
200N
400N
A plumber uses a block and tackle pulley system with 3 pulleys to lift a 600N load. What is the force required to lift the load.
200N
150N
300N
600N
In a plumbing system, what is the pressure at the bottom of a water tank that is 12 meters high, assuming gravity is 9.81 m/s²?
117.72 N/m²
1.22N/m²
11,772 N/m²
1,177.2 Pa
A plumbing system has a water column with a head of 20 meters. What is the pressure at the bottom of the column in bar, assuming the density of water is 1000 kg/m³ and gravity is 9.81 m/s²?
0.2 bar
2 bar
0.02 bar
20 bar
A cistern holds 25 litres of water. What is the force exerted by the water as it leaves the tap, assuming gravity is 9.81 m/s²?
245.25 N
25 N
2.54N
2.45N
Label these materials into Conductors and Insulators
Copper
Silver
Aluminium
Rubber
Plastic
Glass
Identify
Temporary Earth Bonding Clamps
Crocodile Clips
Jump Leads
Equipotential Bonding Clamps
What two things does the MCBO include?
Equipotential Bonding
Line Conductor
MCB
RCD
