A 4.0 g Pin-Pong ball is attached by a thread to the bottom of a beaker. When the beaker is filled with water so that the ball is totally submerged, the tension in the thread is 0.028 N. (a) Determine the radius of the ball. The volume of a sphere is V =4πr3/3 (b) If the string is cut, what volume of the Ping Pong is submerged.

A scientist is calculating the density of an ore sample. The scien- tist measures that the ore sample weighs 22.4 N in air. When the sample is suspended by a thin light cord and totally immersed in water, the tension in the cord is 14.2 N. What is the density of the ore sample that the scientist calculates. You can assume that any buoyant force from air is negligible.

On another planet that you are exploring, a large tank is open to the atmosphere and contains ethanol. A horizontal pipe of cross-sectional area 7.0×10−4m27.0×10−4m2 has one end inserted into the tank just above the bottom of the tank. The other end of the pipe is open to the atmosphere. The viscosity of the ethanol can be neglected. You measure the volume flow rate of the ethanol from the tank as a function of the depth hh of the ethanol in the tank. If you graph the volume flow rate squared as a function of hh, your data lie close to a straight line that has slope 2.09×10−5m5/s22.09×10−5m5/s2.   What is the value of gg, the acceleration of a free-falling object at the surface of the planet? Express your answer with the appropriate units.

A partially filled bucket of water sits on a scale and its weight is 3.8 N.  A piece of metal is suspended from a thread and completely immersed in the bucket (but does not touch the bottom).  The scale now reads 7.3 N.  Find the volume of the metal.