20th Century
Heat in modern terms, is generally defined as a type of energy transferred due to a temperature difference or that generated by friction, etc.
Read more about this topic: History Of Heat
Famous quotes containing the word century:
“In the nineteenth century ... explanations of who and what women were focused primarily on reproductive events—marriage, children, the empty nest, menopause. You could explain what was happening in a woman’s life, it was believed, if you knew where she was in this reproductive cycle.”
—Grace Baruch (20th century)