Why does glycerine need the least mass pieces to lift the paper
Glycerine has a high density compared to other liquids such as water. Density is the ratio of mass to volume, and since glycerine has a higher density, it has a greater mass for a given volume. When placed on a piece of paper, the glycerine exerts a force on the paper due to its weight. Therefore, a small amount of glycerine can have enough mass to generate a force that lifts the paper.
In contrast, other liquids like water have a lower density and therefore a lower mass for a given volume. This means that a larger volume or mass of water would be needed to exert the same force as glycerine. Hence, glycerine requires the least mass pieces to lift the paper compared to other liquids.