Science Test 3
a bubble of air released from the bottom of a lake
becomes larger as it rises
which is larger fahrenheit or celsius
celsius
a substance can absorb heat energy by the process of
conduction, convection, radiation
on a windy day, atmospheric pressure
decreases
when the same amount of heat is added to each of the two containers of water, the temperature increase in each will
depend on the amount water in each
when gas in a container is squeezed to half its volume, its density
doubles
suppose water from a tall tower supplies a nearby home if water faucets upstairs and downstairs are turned fully on will more water per second flow from the downstairs or the upstairs faucet or will water flow in each be the same
downstairs
in a hydraulic device it is impossible for the
energy output to exceed energy input
when water at 4C is heated it expands when water at 4C is cooled it
expands
which is larger fahrenheit or kelvin
fahrenheit
In which of the following is intermolecular bonding weakest
gases
if the volume of an object were to double while its mass stays the same its density would
halve
if a good absorber of radiant energy were a poor emitter its temperature compared with its surroundings would be
higher
when a boat sails from fresh water to salt, the boat will float
higher in the water
compared to a giant iceberg, a hot cup coffee has
higher temperature, but less thermal energy
Which of the following normally warms up faster when heat is applied
iron
when you squeeze a party balloon to 0.25 its volume the pressure in the balloon
is 4 times greater
your feet feel warmer on a rug than on a tile floor because the rug
is a better insulator than tile
ice cubes submerged at the bottom of a liquid mixture indicate that the mixture
is less dense then ice
water with air bubbles flows through a pipe that gets narrower in the narrow region the water gains speed and the bubbles are
larger
the energy involved in a phase change is called the
latent heat
it takes longer time to cook eggs by boiling in the mountains compared to sea level is because
low boiling temperature of water
a substance that heats up relativity quickly has a
low specific heat capacity
Reason why people can walk barefoot on red hot coals of wood without burning their feet
low thermal conductivity of the coals
there is twice as much molecular kinetic energy in 2 liters of boiling water as in 1 liter of boiling water. which will be the same for both
temperature
heat energy travels from an object with a high
temperature to an object with lower temperature
the reason a life jacket helps you float is
the density of both you and th jacket together is less than your density alone
the reason a life jacket helps you float is
the density of both you and the jacket together is less than your density alone
an egg is placed at the bottom of a bowl filled with water. Salt is slowly added to the water until the egg rises and floats. From their experiment one concludes
the density of salt water exceeds the density of the egg
Why Sparklers don't harm you
the energy per molecule is high, but the total energy transferred is small
does a 3 meter deep lake or a 6 meter deep small pond exert more pressure on a dam
the six meter deep small pond
the volume of water displaced by a floating 20 ton boat is
the volume of 20 tons of water
two cans are placed apart on straws when air is blown in between the cans, what will they do
they will move toward each other
if you squeeze an air filled balloon to one third its volume air pressure inside is about
three times as much
heat will not flow spontaneously from a colder to a warmer body
true
which has the higher specific heat water or land
water
the greater the temperature difference of two objects the more rapidly heat energy will be transferred
True
if you hold one end of a metal bar against a piece of ice, the end in your hand will soon become cold, does cold flow from the ice to your hand
no
two people are drinking soda using straws. do they suck the soda up. could they drink soda this way on the moon
no they reduce air pressure in the straw and the atmospheric pressure pushes the soda up. No they could not do the same thing on the moon
one celsius unit is equivalent to
one Kelvin degree
if a hole is punched in the side or bottom of a boat water spurting in will be
perpendicular to the surface
what happens to the internal water pressure in a narrowing pipe of moving water
pressure is less
the lowest temperature possible in nature is
-273 degrees C
one liter of water has a mass of
1 kg
which of these has the greatest density
100kg of lead
mercury has density of 13.6 grams per cubic centimeter how much heaver is it than one cubic centimeter of water
13.6 times heaver
before ice can form on a lake, all the water in the lake must be cooled to
4 degrees C
you heat a half cup of tea and its temperature rises by 8C how much will the temperature rise if you add the same amount of heat to a full cup of tea
4C
why will spraying fruit trees with water before frost help to protect the fruits from freezing
As the water freezes, it loses heat to the cold air, but at the same time, it loses heat to the leaves, stems and fruit of the tree too, so it actually warms up the tree a small amount as well. Once the ice is frozen on the tree, it also acts as an insulator to prevent more cold from getting to the tree itself. water is a great insulator
why is it important to protect water pipes so they do not freeze
Because water expands when it is frozen and this increased pressure will cause the pipes to break.
Bermuda is close to north Carolina but unlike north Carolina it has a tropical climate year round. why?
Bermuda is an island. the surrounding water warms it when it might be too cold, and coolsit when it might be too warm
which is larger celsius or kelvin
Celsius
absolute zero refers to 0C
False it is 0k
would it be slightly more difficult to draw soda through a straw at sea level or on top of a very high mountain
It would be harder on the top of a mountain because the pressure of the atmosphere is lower the higher you go. The atmospheric pressure pushes on the surface of the liquid when you suck which helps the liquid move up the straw. At sea level, the pressure is fourteen and a half pounds per square inch and reduces as you move higher.
which has the greater amount of internal energy an iceberg or a cup of hot coffee
The hot coffee has a higher temperature, but not a greater internal energy. Although the iceberg has less internal energy per mass, its enormously greater mass gives it a greater total energy than that in the small cup of coffee.
why is an umbrella in danger of being turned inside out on a windy day
The wind moving over the top of the umbrella exerted less pressure than the still air beneath. The still air pushed the umbrella up from below.
the reason a person finds it easier to float in salt water compared with fresh water is that in salt water
a smaller volume of water id displaced
When a liquid changes phase to a gas it
absorbs energy
an umbrella tends to move upwards on a windy day principally because
air pressure is reduced over the curved top surface
if you want to cook eggs by boiling them while in the mountains, then compared to sea level cooking you should
boil the eggs for a longer time
which has the greater density a lake full of water or a cup full of lake water
both have the same density
at which hole in the cup is there more pressure on the water shooting out of the hole
bottom hole
In which situation below did conduction take place
burning yourself on a hot stove
when an object is partly or wholly immersed in a liquid, it is buoyed up
by a force equal to the weight of liquid desplaced
when a sample of 0C water is heated it first
contracts
when a bimetallic bar made off copper and iron strips is heated the bar bends towards the iron strip the reason for this is
copper expands more than iron
If earth radiated more energy than it absorbs from the sun earths average temperature would
decrease
which of the following does not emit radiation
everything emits radiation
when a sample of 4C water is cooled it
expands
a boat loaded with scrap iron floats in a swimming pool. when iron is thrown overboard, the pool level will
fall
a floating ice cube contains small pieces of iron after melting the water level will
fall
radiation can travel in a vacuum
false
sand has higher heat capacity than water
false water has a much higher heat capacity
ring is hot the room temperature ball
fits into the hole with more room to spare
when a hot cup is filled with cold water the direction of heat flow is
from the cup to the water
suppose you rapidly stir some raw eggs with an eggbeater the temperature of the eggs will
increase
as a system becomes more distorted, entropy
increases
when work is done on a system compressing air in a tire pump for example the temperature of the system
increases
your garage gets messier each week in this case the entropy of your garage is
increasing
a suction cup sticks to a wall it is
pushed to the wall by the atmosphere
the silver coating on the glass surfaces of thermos bottle reduces energy that is transferred by
radiation
air speeds up as it is blown across the top of the vertical tube. How does this affect the air pressure in the vertical tube, and what then occurs
reduced air pressure in the tube lets atmospheric pressure on the liquid surface push liquid up into the tube where it joins the jet of air in a mist
When a gas is changed to a liquid phase, the gas
releases energy
heat energy is measured in units of
remains the same
when an ice cube in a glass of water melts the water level
remains the same
when stringing telephone lines between poles in the summer it is advisable to allow the lines to
sag
Consider two tubes filled with water at the same height one with fresh water water and the other with salt water the pressure is greater at the bottom of the tube with
salt water
a 10kg load on the left piston will support a 500 kg load on the right piston. how does the pressure of fluid against the lower part of the left piston compare with the pressure against the lower right piston
same pressure on each
when thermal insulation such as spun glass or rock wool is placed beneath the roof of a house then in cold weather the insulation will
slow the flow of heat from inside the house to the outside
it is commonly thought that a can of beverage will cool faster in the coldest part of the refrigerator. knowledge of newtons law of cooling
supports this knowledge
The pressure in a stream water is reduced as the stream speeds up. How then can a stream of water from a fire hose actually knock a person off his or her feet
the pressure due to waters change in momentum can be much greater than the waters internal pressure
consider two mercury barometers one with twice the cross sectional area of the other. neglecting capillary mercury in the smaller tube will rise
the same height as in the larger tube
when a chocolate bar is cut inhale its density is
unchanged
completely submerged object always displaces its own
volume of fluids
during a very cold winter, water pipes sometimes burst the reason for this is
water expands when freezing
A dam is thicker at the bottom that at the top because
water pressure is greater with increasing depth
atmospheric pressure is caused by the
weight of Earths atmosphere
a balloon is buoyed up with a force equal to the
weight of air it displaces
a fish normally displaces its own
weight of water and volume of water
is there a buoyant force acting on your classmate at this moment?
yes but it is insignificant compared with their weights