Chapter 8 Test
A buoyant force acts in the opposite direction of gravity. Therefore, which of the following is true of an object completely submerged in water? a. The net force on the object is smaller than the weight of the object. b. The net force on the object is larger than the weight of the object. .c. The net force on the object is equal to the weight of the object. d. The object appears to weigh more than it does in air
a
What factors affect the gauge pressure within a fluid? a. fluid density, depth, free-fall acceleration b. fluid volume, depth, free-fall acceleration c. fluid mass, depth, free-fall acceleration d. fluid weight, depth, free-fall acceleration
a
Which of the following is a fluid? a. helium b. ice c. iron d. gold
a
Which of the following is not an example of turbulent flow? a. a river flowing slowly in a straight line b. a river flowing swiftly around rocks in rapids c. water flowing unevenly from a fully opened faucet d. smoke twisting as it moves upward from a fire
a
A cube of wood with a density of 0.780 g/cm^3 is 10.0 cm on each side. When the cube is placed in water, what buoyant force acts on a wood? a. 7.65 x 10^3 N b. 7.65 N c. 6.40 N d. 5.00 N
b
How does a liquid differ from a gas? a. A liquid has both definite shape and definite volume, whereas a gas has neither. b. A liquid has definite volume, unlike a gas. c. A liquid has definite shape, unlike a gas. d. A liquid has definite shape, whereas a gas has definite volume
b
Which of the following properties is not characteristic of an ideal fluid? a. laminar flow b. turbulent flow c. non viscous d. incompressible
b
Which of the following statements is not correct? a. A fluid flows. b. A fluid has a definite shape. c. Molecules of a fluid are free to move past each other. d. A fluid changes its shape easily
b
Why does an ideal fluid move faster through a pipe with decreasing diameter? a. The pressure within the fluid increases b. The pressure within the fluid decreases. c. The pipe exerts more pressure on the fluid. d. The fluid moves downhill
b
For incompressible fluids, density changes little with changes in a. depth. b. temperature. c. pressure. d. free-fall acceleration.
c
If the air pressure in a tire is measured as 2.0 x 10^5 Pa, and atmospheric pressure equals 1.0 x 10^5 Pa, what total pressure does the air within the tire exert outward on the tire walls? a. 1.0 x 10^5 Pa b. 2.0 x 10^5 Pa c. 3.0 x 10^5 Pa d. 4.0 x 10^5 Pa
c
Which of the following statements is true according to Pascal's principle? a. Pressure in a fluid is greatest at the walls of the container holding the fluid. b. Pressure in a fluid is greatest at the center of the fluid. c. Pressure in a fluid is the same throughout the fluid. d. Pressure in a fluid is greatest at the top of the fluid.
c
Why does the lift on an airplane wing increase as the speed of the airplane increases? a. The pressure behind the wing becomes less than the pressure in front of the wing. b. The pressure behind the wing becomes greater than the pressure in front of the wing. c. The pressure above the wing becomes less than the pressure below the wing. d. The pressure above the wing becomes greater than the pressure below the wing.
c
A water bed that is 1.5m wide and 2.5m long weighs 1055 N. Assuming the entire lower surface of the bed is in contact with the floor, what is the pressure the bed exerts on the floor? a. 250 Pa b. 260 Pa c. 270 Pa d. 280 Pa
d
Which of the following is not an example of laminar flow? a. a river moving slowly in a straight line b. smoke rising upward in a smooth column through air c. water flowing evenly from a slightly opened faucet d. smoke twisting as it moves upward from a fire
d
Which of the following statements about floating objects is correct? a. The object's density is greater than the density of the fluid on which it floats. b. The object's density is equal to the density of the fluid on which it floats. c. The displaced volume of fluid is greater than the volume of the object. d. The buoyant force equals the object's weight
d