1. A particular object weighs 343 N In air and 144 N when immersed in alcohol of density 0.7 g/cm3. What are the volume and the density of the object?
2. In order to lift a wire ring of radius 2.25 cm from the surface of a container of blood plasma, a vertical force of 1.30 X 10-2 N greater than the weight of the ring Is required. Calculate the surface tension of blood plasma from this information.
3. Water is transported upward in a plant through xylem tissue, which consists of cells of 1 mm length and a diameter of 65 µm. The xylem cells are attached to each other to form a channel. To what maximum height can water rise in these xylem channels due to capillarity? For those Interested: Confirm this result with a simple experiment: Cut and split the stem of a flower with white petals (e.g., a dahlia or a carnation) and place one half the stem in a glass with dilute red ink and the other half in a glass with dilute blue Ink. After several hours the flower will be half red and half blue.