Plumbing science revision

Which of the following materials is used for its ductile properties?

• Cast-iron

• Ceramic

• PVC

• Copper

During electrolytic action, which one of the following would occur?

• Anode will gradually destroy the cathode

• Electrolyte will destroy the cathode

• Electrolyte will be used up and disappear

• Cathode will gradually destroy the anode

Pitting is a form of Corrosion?

• True

• False

Which one of the following materials will reflect the greatest amount of radiant heat?

• Oxidised copper

• Cast iron

• Galvanised steel

• Polished aluminium

An alloy is a mixture of two or more metals?

• True

• False

Which one of the following identifies a method of increasing hot water system efficiency?

• Increasing system flow rate

• Increasing system pressure

• Adding pipe insulation

• Adding corrosion inhibitor

Which of the following has a combustion temperature of 1930°C?

• Natural gas

• Acetylene

• Propane

• Butane

273K is the equivalent of how many °C?

• -10

• 0

• 10

• 100

One Pascal is equal to one

• 1 Bar

• 1 Gauge

• 1 N/m2

• 1 Kg/m2

The formula to calculate total pressure is intensity of pressure x base area. What is the approximate total pressure acting on the base of a cistern that measures 0.5m x 1.0m, if the intensity of pressure on the base is 19.62 kPa/m2?

• 19.62kPa

• 9.81kPa

• 4.90kPa

• 39.24kPa