Scientific Principles Mock 3 - Past Paper PDF

## SCIENTIFIC PRINCIPLES MOCK 3 1. In degrees Celsius, water boils at - 100°C. 2. When a substance changes state from a liquid to a gas, the molecules - move further apart. 3. An instantaneous water heater requires a minimum pressure of 0.7 Bar to operate satisfactorily. If this was to b...

## SCIENTIFIC PRINCIPLES MOCK 3 1. In degrees Celsius, water boils at - 100°C. 2. When a substance changes state from a liquid to a gas, the molecules - move further apart. 3. An instantaneous water heater requires a minimum pressure of 0.7 Bar to operate satisfactorily. If this was to be supplied from an existing cold water cistern, how high would the cistern need to be to provide the minimum pressure? - 7.0 metres. **Figure 1** - Tank A: 3m high - Tank B: Length = 1.5m, Width = 1m 4. Refer to Figure 1. Which one of the following calculations would give the correct intensity of pressure of water at the base of closed tank B? - 3 m X 1.5 m X 1 m X 9.81 kN/m². 5. Which one of the following factors has the most influence on the frictional resistance within a cold water pipework system? - The number of elbows in the pipework. 6. Which domestic appliance listed below uses the principle of siphonage? - Double trap WC. 7. Which one of the following types of temperature measurement device would be most suitable for use within a thermostatic radiator valve? - Phial of heat sensitive gas. 8. The energy used to heat 1 kg of water by 2°C is 8.372 kJ. The specific heat value for water is - 4.186 kJ/kg / °C 9. Which one of the following most accurately describes the way in which heat is transferred by convection? - The transfer of heat through a fluid substance, usually a liquid or gas. 10. Water from an area which has a limestone and chalk bedrock, is most likely to be - alkaline. **Figure 2** - Groove labelled A found on overlapped lead sheeting 13. Refer to Figure 2. The groove labelled A is found on overlapped lead sheeting to prevent - leakage due to capillary attraction. 14. What formula is used to calculate a fuse size in amps? - I = W / V 15. Which one of the following is a ferrous metal? - Steel. 16. Which one of the following materials expands the most when heated? - Lead. 17. The common name given to the protective barrier that forms on copper and lead when exposed to the atmosphere is - patina 18. The SI unit for the measurement of current is - Amp 19. The fuse size which should normally be used to protect the lighting circuit at the consumer unit is - 15 amp 20. If a magnet is passed in and out of, or around, a copper wire wound around a soft iron core, the electricity generated would be - an alternating current.