Why? The density remains the same because cutting the object in half will divide the mass & volume by the same amount. Also, the density of a substance remains the same no matter what size it is. All matter has its own unique density.

Does density always stay the same?

Density is an intensive property. This means that regardless of the object's shape, size, or quantity, the density of that substance will always be the same. Even if you cut the object into a million pieces, they would still each have the same density.

Does density never change?

Does size (or amount) affect density? ... However, the density does not change. This is because the mass and volume increase at the same rate/proportion! Even though there is more molasses (mass) in test tube A, the molasses also takes up more space (volume).