remains the same
When an ice cube in a glass of water melts, the water level in the glass ____________________.
the distance through which the force acts.
A certain hydraulic press multiplies force by 10. This multiplication is done at the expense of ____________________.
A water strider, an insect that skates on water, is supported by ____________________.
less or equal to the air displaced
You would float like a balloon in air if your weight was ____________________.
increase by 125%
If you squeeze a bag of air to 80 percent its volume, pressure inside will ____________________.
When water flows into a pipe that narrows to half its cross-sectional area, the speed of the water ____________________.
When a fluid speeds up in going over a surface, pressure of the fluid against that surface ____________________.
How much lift will be exerted on airplane wings of 100 m2 area when the difference in air pressure below and above is 4% of atmospheric pressure? (atmospheric pressure is about 105 N/m2)
low specific heat capacity
A substance that heats up relatively quickly is said to have a ____________________.
When water at 4°C is warmed, it expands. When water at 4°C is cooled, it ____________________.
the low conductivity of wood, even when hot.
The main factor that allows firewalkers to walk barefoot on red hot coals of wood is ____________________.
migrate to the ceiling
If at a party you let helium out of a balloon, it will very soon ____________________.
high-frequency light in and preventing low-frequency radiation from getting out.
In a florist's greenhouse, glass acts as a one-way valve, letting ____________________.
have a wide variety of speeds.
In a container of room-temperature water, the molecules of water ____________________.
The faster ones.
Which molecules in a container of water are the most likely to evaporate and carry energy away with them?
When a vapor or gas changes to the liquid phase, the vapor or gas ____________________.
When air pressure is increased on the surface of water, the temperature required for boiling ____________________.
slow-moving water molecules sticking to one another.
Morning dew on the grass results from ____________________.
lower in the water
Compared to an empty ship, will a ship loaded with a cargo of Styrofoam float lower in water or higher in water?
water pressure depending on depth.
Everybody knows that "water seeks its own level," but very few people know why water seeks its own level. The reason has most to do with
An astronaut on Earth notes that in her soft drink an ice cube floats with 9/10 its volume submerged. If she were instead in a lunar module parked on the Moon, the ice in the same soft drink would float with
Consider a boat loaded with scrap iron in a swimming pool. If the iron is thrown overboard into the pool, will the water level at the edge of the pool rise, fall, or remain unchanged?
The weight of the stand and suspended solid iron ball is equal to the weight of the container of water as shown above. When the ball is lowered into the water the balance is upset. The amount of weight that must be added to the left side to restore balance, compared to the weight of water displaced by the ball, would be
shows an increase
Gently push down on the pan of the scale and the display shows an increase in force. Likewise if you do the same on the rim of the beaker. But what if you immerse your fingertip in the water. without touching the beaker? Then the scale reading
Consider a solid brass cube and a solid brass sphere that have equal surface areas. When both are completely submerged in water, the one experiencing the greater buoyant force is the
Consider a Ping-Pong ball floating in a glass of water that is in an air-tight chamber. When air pressure is increased in the chamber, does the ball float lower, higher, or as before?
Consider an air-filled balloon weighted so that it is on the verge of sinking—that is, its overall density just equals that of water.Now if you push it beneath the surface, it will
upset and the stick rotates clockwise.
A pair of identical balloons are inflated with air and suspended on theends of a stick that is horizontally balanced. When the balloon on the left is punctured, the balance of the stick is
Water with air bubbles flows through a pipe that becomes narrower. In the narrow region the water gains speed and the bubbles are
You're driving in a convertible car with the top up and the windows closed. You note that the fabric top puffs up. To explain this interesting phenomenon you invoke
Water molecules in ice link together to form an open-spaced structure. The open pockets in the structure are what makes ice less dense than water, which is why ice floats on water. To be sure you interpret this correctly, answer this: What's inside the open pockets?
Suppose in a restaurant your coffee is served about 5 or 10 minutes before you are ready for it. In order that it be as hot as possible when you drink it, should you pour in the room-temperature cream right away or when you are ready to drink the coffee?
Hot water/steam radiators are common fixtures that nicely warm the interiors of buildings. These radiators warm a room primarily via
When evaporation of water occurs, the faster-moving (more energetic) water molecules escape the liquid and become molecules in the air. The average kinetic energy of molecules remaining in the liquid is lowered. The water is cooled.Normally, the air that receives the escaping molecules is
A piece of metal and a piece of wood of equal mass and equal temperature are removed from a hot oven and dropped onto blocks of ice. Which will melt more ice before cooling to the ice temperature?
the buoyant force on an object is equal to the weight of the fluid displaced by the object
the pressure applied to a motionless fluid confined in a container is transmitted undiminished throughout the fluid.
force that acts on the surface of a liquid and that tends to minimize the area of the surface
As the velocity of a fluid increases, the pressure exerted by the fluid decreases
(cryogenics) the lowest temperature theoretically attainable (at which the kinetic energy of atoms and molecules is minimal)
the movement of thermal energy from a substance at a higher temperature to one at a lower temperature
specific heat capacity
the amount of heat energy required to raise the temperature of one gram of substance by one degree celsius
Newton's law of cooling
The rate loss of heat from an object is proportional to the temperature difference between the object and its surroundings
Green house effect
The warming of the surface and lower atmosphere of the Earth that occurs when water vapor, carbon dioxide, and gases absorb and radiate thermal energy.
The process of melting under pressure and the subsequent refreezing when the pressure is removed.
latent heat of fusion
The amount of energy required to change a unit mass of a substance from solid to liquid