Energy Resources and Energy Transfers
4 marks · EasyA metal kettle is used to boil water for tea in a kitchen. The base of the kettle gets very hot while it is on the stove.
Name the process by which thermal energy is transferred through the metal base of the kettle.
State why the kettle feels hot to the touch after boiling.
Give one way the kettle could be designed to lose less thermal energy to the surroundings.
Which unit would you use to measure the amount of energy transferred by the kettle?
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) conduction
(b) Thermal energy is conducted from the hot base to the outside surface of the kettle.
(c) Add insulation (such as a double wall or a thermal sleeve) to reduce heat loss.
(d) joule (J)
Common mistakes: confusing conduction with convection; incorrect units
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Correctly names conduction as the process.
B1 (b) · 1 mark · States that heat is conducted to the kettle's surface.
B1 (c) · 1 mark · Names any valid insulation/reduction of heat loss method.
B1 (d) · 1 mark · Gives joules (J) as the unit for energy transferred.
Worked solution
a) The process is conduction, which transfers heat through the metal.
b) The outer surface becomes hot as energy is conducted from the base through the metal to the outside.
c) An insulating layer, such as a double wall or foam sleeve, reduces energy transfer to the air.
d) The unit used is the joule (J).