An electric convector heater is used to warm the air in a small office.
State the main method of thermal energy transfer throughout the air in the office.
Explain how the heater warms all the air in the office.
The power of the heater is 1.8 kW when it is connected to a mains supply with an e.m.f. of 240 V.
Show that the current in the heater is 7.5 A.
The plug connecting the heater to the mains supply is fitted with a fuse. Fuse ratings of 3 A, 5 A, 10 A, and 13 A are available. State which fuse should be used and explain your choice.
301 exam-style questions on CIE IGCSE Physics 2.3 Transfer of thermal energy, covering 2.3.1a Thermal conductors and thermal insulators, 2.3.1b Explaining thermal conduction, 2.3.2 Convection, 2.3.3a Thermal radiation, 2.3.3b Surface colour and texture, 2.3.3c Rate of emission and absorption of radiation, and 2.3.4 Consequences of thermal energy transfer. Each one has a worked solution and a mark scheme showing where the marks go.