In 1653, which French scientist observed that if some pressure is applied to any point of an incompressible fluid, the same pressure is transmitted to all points of the fluid and to the walls of the vessels ?

Blaise Pascal

The correct answer is option 3. Blaise Pascal.

In 1653, the French scientist who observed that if pressure is applied to any point of an incompressible fluid, the same pressure is transmitted to all points of the fluid and to the walls of the vessels was Blaise Pascal.

Blaise Pascal, a French mathematician, physicist, and philosopher, is credited with Pascal's law, also known as the principle of transmission of fluid-pressure. Pascal's law states that pressure applied to a confined fluid is transmitted undiminished to every part of the fluid and to the walls of the container. This observation laid the foundation for the study of hydrostatics and had significant implications in various fields of science and engineering.