And V bar is basically one divided by the density of the particle. So this is equal to so let's call this row the density of the fluid divided by so z is the density of the fluid. And this V bar is basically one divided by a density of the particle. So multiplied by one divided by a density of the particle, which is equal to this right over here. So we see that this product is simply the ratio of the densities of the fluid to our particle. Now, if the density of the fluid is equals the density of the particle, then this ratio is simply equal to one.