Heat Questions - GCSE Level
Q12. (a) Heating food in a saucepan over a gas flame is inefficient. Suggest why.
(b) A new saucepan has been designed that heats up food much faster than a traditional saucepan. The diagram below shows the two saucepans.
Describe how the features of the new saucepan cause the food to heat up faster than when the food is heated in the traditional saucepan.
(c) State the relationship between the temperature of the saucepan and the rate at which the saucepan emits infrared radiation.
(d) A new design for a kettle has also been suggested. It is made from two layers of plastic separated by a vacuum. After the water in the kettle has boiled, the water stays hot for at least 2 hours.
Here is a diagram of the design.
Explain why the vacuum reduces energy transfer to the surroundings and keeps the water warm for a longer time than a traditional kettle.
(8 marks total)