When the following are placed in water, for which of them will the buoyant force be more than as its weight?
A) an ice cube
B) a piece of frozen glycerin
C) a gold ring
D) a piece of aluminum foil
2. Sometimes when I get in my swimming pool I take a plastic cup filled with wine with me. The cup holds 400 cc of wine. I have observed that the cup sinks when it is full of wine, but floats after I have drunk at least 1/4 of it. What is the mass of the cup? Assume that the specific gravity of the wine is 1.04.
3) A car with mass 2000kg is held at a height of 1.8 meters by a hydraulic lift. The surface area of the piston inside the lift is 300cm², and the surface area of the input tube at the bottom of the lift is 6 cm². What force must be exerted on the fluid in the input tube to hold the car up? (Neglect the mass of the fluid itself.)