Exam 15: Fluid Mechanics

A police crime lab is trying to determine whether someone was murdered or died as a result of an accident.He was struck in the temple by a 4.20 kg sculpture that is alleged to have fallen off a bookcase.The sculpture presumably fell a distance of 1.43 m and the corner that struck him had an area of 0.250 cm².If the time for the sculpture to stop was 1.00 ms,the pressure on his temple,in N/m²,was

A large water storage container is filled to a depth of 3.0 m.The volume above the water is filled with air.In order to pump the water from the container,the air pressure in the container is increased by 3.0 $x$ 10⁵ N/m².What happens to the pressure in the water at a depth of 1.0 m when the air pressure is increased?

Melanie says that when a diver enters an underwater cave of height h,the pressure on her is no greater than $\rho$ _Wgh.Rosalind says that if the bottom of the cave is a distance H below the water surface,the pressure on the soles of the diver's feet can reach $\rho$ _WgH.Which one,if either,is correct? (The density of water is $\rho$ _W. )

Water pressurized to 3.5 * 10⁵ Pa is flowing at 5.0 m/s in a horizontal pipe which contracts to 1/3 its former area.What are the pressure and velocity of the water after the contraction?

A stonecutter's chisel has an edge area of 0.7 cm².If the chisel is struck with a force of 42 N,what is the pressure exerted on the stone?

All people come very close to being able to float in water.What therefore is the volume (in cubic meters)of a 50-kg woman?

An empty spice bottle has an inner volume of 1.31 *10 ^{- 4} m³.It has a mass of 112 g when filled with air,and it displaces 1.63 *10 ^{- 4} m³ of water when fully submerged.What fraction of the total volume of the bottle will be beneath the surface when it is placed in a tank of water?

Air within the funnel of a large tornado may have a pressure of only 0.2 ATM.What is the approximate outward force on a (5 m *10 m)wall if a tornado suddenly envelops the house? (1 ATM = 1.01 *10⁵ N/m². )