fluides, an essay containing various original ideas and new observations. In it he considered air as an incompressible elastic fluid composed of small particles and, carrying over from the principles of solid body mechanics the view that resistance is related to loss of momentum on impact of moving bodies, he produced the surprising result that the resistance of the particles was zero (the thesis that will be discussed in this research paper); the conclusion was known as the dAlemberts Paradox and is not accepted by modern physicists. In the Memoirs of the Berlin Academy he published findings of his research on integral calculuswhich devises relationships of variables by means of rates of change of their numerical valuea branch of mathematical science that is greatly indebted to him. In his Recherches sur diffrents points importants du systme du monde (1754-1756) he perfected the solution of the problem of the perturbations (variation of orbit) of the planets that he had presented to the academy some years before. From 1761 to 1780 he published eight volumes of his Opuscules mathmatiques. Meanwhile, it is to note that dAlembert had a big implication in The Encyclopdie with some of his friends philosophers (Voltaire, Rousseau, Montesquieu)So the various works of dAlembert, made of him a great man of our modern science. But among all this brilliant work, there is one theory that let him perplex as he said himself. This concerns his famous paradox, for he found that: there is no drag on a solid in movement in an irrotational and incompressible flow.During the following pages, we will try to see how the mathematical tools explained this incongruity.DAlemberts Paradox. After a long study of the mathematical theory of fluids, he nonetheless got a negative result. And he ended with the following conclusion:I do not see then, I admit, how one can explain the resistance of fluids by the theory in a satisfactory manner. It seems to me on the cont...
