The da Vinci Code Leonardo da Vinci (1452-1519) is credited with being the first to perfor...

The da Vinci Code Leonardo da Vinci (1452-1519) is credited with being the first to perform quantitative experiments on friction, though his results weren’t known until centuries later, due in part to the secret code (mirror writing) he used in his notebooks. Leonardo would place a block of wood on an inclined

Sketches from the notebooks of Leonardo da Vinci showing experiments he performed on friction plane and measure the angle at which the block begins to slide. He reports that the coefficient of static friction was 0.25 in his experiments. At what angle did Leonardo’s blocks begin to slide?