One day during cooking class, the teacher, Mrs Jones, was sharing her secrets for preparing perfect sauces. When she ordered the class to the stoves to prepare their assignments, she said: “Now don’t forget to use wooden spoons.”

As one of the students stirred his sauce, he contemplated the physics behind the mystery of the wooden spoon and decided it must have something to do with heat conduction. He approached Mrs Jones to test his theory. “Why wooden spoons?” he asked.

“Because,” she replied. “If I have to sit here listening to all your metal spoons banging against metal pots, I’ll go nuts!”