1
If an object has a density equal to the density of water it will.....
neither float nor sink
TRUE or FALSE: Because concrete is much more dense than water, a ship made of concrete won't float.
False
Water pressure on a submerged object is greatest against the ______ of the object.
bottom
If an object has a density greater than the density of water, it will _______.
sink
TRUE or FALSE: The reason objects immersed in a fluid experience an upward buoyant force is because fluid pressure on the bottom of the object is greater than fluid pressure on the top of the object.
True
TRUE or FALSE: The principle reason a hydraulic press works is that it is an exception to energy conservation.
False
The volume of water displaced by a floating 20,000 N boat is the volume of ________ of water.
20,000 N
100
When an ice cube in a glass of water melts, the water level.....
remains the same
TRUE or FALSE: An immersed object is buoyed up by a force equal to the volume of the fluid it displaces.
False
Where is the pressure greater, one meter beneath the surface of Lake Michigan or one meter beneath the surface of a swimming pool?
TRUE or FALSE: Press in a liquid depends on the direction the pressure gauge is pointing.
False
The pressure at the bottom of a jug filled with water does NOT depend on the.....
a. density of water
b. surface area of the water
c. depth of the liquid
d. acceleration due to gravity
e. none of the above
b. surface area of the water
In a hydraulic press operation, it is impossible for the energy ______ to exceed the energy _______.
output...input
Pressure in a liquid depends on what 2 things?
depth & density of the liquid
Where is the buoyant force on a submerged rock greater, near the surface of the fluid or 10 m below the surface?
Neither place----buoyant force is independent of depth
Why does a life jacket help you float?
it decreases your density
Suppose a stone weighs 8 N in the air, but in water it weighs only 5 N. What is the buoyant force acting on the stone?
3 N
If a weight, air-filled balloon sinks in a lake, it will.....
a. by buoyed up with constant force while sinking
b. probably sink to the bottom and rise later
c. always sink to the bottom
d. sink until it reaches equilibrium and then remain at constant depth
c. always sink to the bottom
When you float in salt water compared to floating in fresh water, the buoyant force that supports you is.....
the same
A hydraulic arrangement consists of a water-filled U-tube that is wider on one end than on the other. Pistons are fitted on both ends. To multiply an input force, the input end should be the one having the ________-diameter piston.
smaller
If the part of an iceberg that extends above the water were removed, what would happen to the iceberg?
it would rise
When first put in water, a plastic toy boat will sink until...
a. it displaces a volume of water equal to its own volume
b. the water density equals the density of the boat
c. it displaces a weight of water equal to its own weight
c. it displaces a weight of water equal to its own weight
Pascal's principle says that changes in pressure at any point in an enclosed fluid......
are transmitted to all points in the fluid
A hydraulic press multiplies a force by 100. This multiplication is done at the expense of.....
the distance through which the force acts
A 40,000 N car is lifted on a hydraulic piston of area 1000 square centimeters. How much force on a 10 square centimeter piston is needed to lift the car?
400 N
The buoyant force on an object is least when the object is..
a. submerged near the bottom
b. submerged near the surface
c. partly submerged
c. none of the above
c. partly submerged
A hydraulic press works because liquids transmit ________ undiminished, one piston is _______ than the other piston, and ________ principle is operating.
pressure.......larger.....Pascal's
A floating person, who can just barely float in fresh water, has a mass of 50 kg. Their volume is therefore about......
50 liters