GCSE Questions - Electromagnetic Spectrum



The diagram above shows a way that biscuit manufacturers can cook large quantities of biscuits.

The uncooked biscuits are placed on a moving metal grid. The biscuits pass between two hot electrical heating elements inside an oven. The biscuits turn brown as they cook.

The oven has two control knobs, as shown in in the diagram below.



(a) Which type of electromagnetic radiation makes the biscuits turn brown? [1 mark]

(b) Suggest two ways of cooking the biscuits in this oven, to make them turn browner. [2 marks]

(c) The inside and outside surfaces of the oven are light-coloured and shiny. Explain why. [3 marks]

(Total 6 marks)