Get to know the concept of food energy and the measurement units used to measure it. Relate them to the joule, the usual energy unit in physics that you have already learned. Answer the question.
All living things need energy (metabolism). Plants produce their own energy from sunlight (they are autotrophs) - this process is called photosynthesis. Humans and animals are not capable of photosynthesis and get their energy from food (we are heterotrophs). Energy is stored in chemical bonds and is only released when these chemical bonds are broken.
In a very physics-like language, it can be said that inside us there is an oven with a very peculiar shape and construction, in which we constantly burn fuel, i.e. food, on a "small fire".
In food science, we still talk about the same energy, which has already been mentioned several times in this course. It is possible to easily convert calories into joules and place it in the context of the mind games discussed earlier. For example, you can seriously ask how many packets of halvah are needed to boil a liter of water. This may be a surprising fact for students.