003 Scientific Principles Quiz

Which one of the following is the freezing point of water?

• 0°C.

• 32°C.

• 75°C.

• 100°C.

A change of state in water takes place at which of the following temperatures?

• 25°C.

• 50°C.

• 75°C.

• 100°C.

Water is at its maximum density at which one of the following temperatures?

• 0°C.

• 4°C.

• 25°C.

• 52°C.

What is the intensity of pressure acting on the inlet to the 15 mm tap shown in the following diagram?

Which one of the following pipes of equal length will create the greatest resistance to the flow of water?

• A 22mm pipe which reduces down to 15mm for a quarter of its length.

• A 15mm pipe which contains 4 machine bends.

• A 15mm pipe which contains 2 machine bends and 2 elbows.

• A 15mm pipe which contains 4 elbows.

Which one of the following will cause siphonage to occur from the upper container to the lower container in the following diagram?

• Suction pressure at point B.

• Positive pressure at point B.

• Suction pressure at point A.

• Atmospheric pressure at points A and B.

Which one of the following types of device is used to take temperature measurements of pipe surfaces when commissioning a central heating system?

• Cylinder thermostat.

• Room thermostat.

• Differential digital thermometer.

• Multi-meter.

What is the amount of heat energy required to raise 200 litres of water from 40° to 75°C?

_______kJ/Kg/°C

If the specific heat capacity of water is 4.2 kJ/kg/°C, how much energy is required to heat 240L from 10°C to 60°C?

• 42000kJ.

• 50400kJ.

• 84000kJ.

• 96000kJ.

Conduction occurs by

• heat travelling in straight lines through air

• heat travelling through a solid material

• heat transfer by a chemical reaction

• heat transfer by motion of a fluid.