Why is the sky blue?

Why is the sky blue, the leaves green and the blood red? What do clouds weigh and why don't they just fall down? And why is the freedom above them not so boundless after all? Why is a "quantum leap" in physics the complete opposite of what it means in everyday language? Friends Tina-Jasmin and Johanna, students Yvonne and Lukas and Jean Baptiste from the Congo talk about their everyday experiences and use them to explain the physics they encounter - sometimes without realising it. A series of amusing little stories from everyday life deal with encounters with nature and technology. They read easily and fluently - on a train journey, on holiday, on the sofa or when the television is too boring. Each story deals with a different topic and can be read on its own. For readers who want to know a little more about how the numerical examples come about, most of the stories are followed by a short "To do the maths" section. This can sometimes be very useful for teachers, pupils or students. Of course, each story can also be read without doing the maths.