So S is our sedimentation coefficient and it is given in units known as cevetberg units. Now M is the mass of that particular particle that we are examining. In this particular case, the mass is the mass of this blue biological particle. Now V bar is known as the partial specific volume and more specifically, it's the reciprocal of the density of that particle. So V bar is equal to one divided by the density of that particle. Now this row is basically the density of our medium and F is basically the frictional coefficient of that particle.