Physical Science Exam 3

When work is done BY a system, compressing air in a tire pump, for example, the temperature of the system?

Decreases

1 liter of water in left pot with 3 liters of water in the right pot. Both pots of water absorb the same quantity of heat. Temperature increase three times as much in the pot with the smaller amount of water. When the same amount of heat is added to each of the two containers of water, the temperature increases in each will?

Depend on the amount of water in each

What happens to the density of water when it is LESS than 4 degrees C?

It has greater density

What happens to the density of water when it is MORE than 4 degrees C?

It has less density

What is it not correct to say about heat?

It is not correct to say that a substance contains heat. The substance has internal energy, not heat. The word "heat" is used only when referring to the energy actually in transit between substances. -The heat transfer in the above example ceases when the objects in thermal contact are at the same temperature also known as a state of thermal equilibrium

What is heat energy?

It is the energy that flows from a high temperature object to a lower temperature object because of the difference in temperatures

The greatest expansion of water occurs when?

It turns to ice

How do you convert Celsius to Kelvin?

K=C+273

If a room is cold it is due to a?

Lack of adequate thermal energy

When an iron ring is heated, the hole becomes?

Larger

Microscopic slush in water tends to make the water?

Less dense

Hot sands cools off faster at night than plants and vegetation. This indicates the specific heat capacity for sand is?

Less than that of plants

Water at 4 degrees C will sink to the bottom of a pond because?

Like a rock, it is denser than surrounding water

A substance that heats up rather quickly has a?

Low specific heat capacity

the fact that desert sand is very hot in the day and very cold at night is evidence that sand has a?

Low specific heat capacity

In nature, high-quality energy tends to transform to?

Lower-quality energy

What is a thermometer?

Measures temperature by expansion or contraction of a liquid (mercury or colored alcohol) -Reading occurs when the thermometer and the object reach thermal equilibrium

What is heat transfer in metals?

Metals are generally good conductors of heat, or thermal conductors. Metals have a large number of electrons that are fee to move around. These free electrons are primarily responsible for the good heat conduction in metals.

Whether one object is warmer than another object has most to do with?

Molecular kinetic energy

The fact that gasoline will overflow from an automobile tank on a hot day is evidence that the expansion of gasoline is?

More than the tank material

What is thermal expansion?

Most substances expand when heated and shrink when cooled. Microscopically this is due to the fact that the molecules in the hot substance jiggle faster and farther apart.

What is the third law of thermodynamics?

No system can reach absolute zero -Experimentally, absolute zero has never been observed. In low temperature experiments, scientists have come close to absolute zero - within about 0.000000001 (one billionth) of the Kelvin

What is heat transfer among nonmetals?

Nonmetals, such as wood and cloth, have relatively few free electrons. The absence of this transfer mechanism makes them poor heat conductor relative to metals. A poor heat conductor is called thermal insulator.

What happens with the heat of a hot object and a cold object?

Obviously the temperature of the hot object will decrease and the temperature of the cold object will increase. In the microscopic level the atoms and molecules of the hot object lose kinetic energy and the ones in the cold objects gain kinetic energy.

Which is the smallest unit of measurement for temperature?

One Fahrenheit degree

When you remove a electrons from a teal cup, the cup becomes?

Positively charged

When stringing telephone lines between poles in the summer, it is advisable to allow the lines to?

Sag -Telephones lines are longer in warmer summer and shorter in cold winter. Hence, they sag more on hot summer days than in winter. If the lines are not strung with enough sag in summer they might contract too much and snap during the winter-especially when carrying ice

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 -Average kinetic energy of molecules is the same, which means temperature is the same for both

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 -Average kinetic energy of molecules is the same, which means temperature is the same for both

What is thermal equilibrium?

Temperature is the same everywhere (30 degrees C)

What is temperature?

The average kinetic energy of all particles inside a substance

If a red hot thumbtack is immersed in warm water, the direction of heat flow will be from the?

The red hot thumbtack to the warm water

Heat is simply another word for?

Thermal energy that flows from hot to cold

The fact that a thermometer "takes its own temperature" illustrates?

Thermal equilibrium

The thermal energy in a substance is related mostly to the?

Total kinetic energy of particles

Heat is thermal energy that matter?

Transfers

The kind of molecular motion having most to do with temperature is?

Translational motion

To say something is twice as hot an another suggests the hotter thing has?

Twice the thermal energy

Which of the following contracts most when the temperature is decreased? Equal volumes of?

Water

The first law of thermodynamics is a restatement of the?

Conservation of energy

The lowest temperature possible in nature is?

-273 degrees C

What is the Celsius scale?

0 degrees C for freezing point of water to 100 degrees C for boiling point of water -Named after Anders Celsius

You heat a half-cup of tea and its temperature rises by 4 degrees C. How much will the temperature rise if you add the same amount of heat to a full cup of tea?

2 degrees C

What is the Kelvin scale?

273 K for freezing point of water to 373 K for boiling point of water -Kelvin also known as the absolute temperature -Named after Lord Kelvin

What is the Fahrenheit scale?

32 degrees F for freezing point of water to 212 degrees F for boiling water -Named after G. D. Fahrenheit

You heat a half-cup of tea and its temperature rises by 8 degrees C. How much will the temperature rise if you add the same amount of heat to a full cup of tea?

4 degrees C

Increasing the temperature of 50 grams of water by 1 degree C requires?

50 calories

The temperature of water rises when 2 calories are added. It will rise the same when?

8.38 J are added

A bimetallic strip consists of a strip of metal composed of?

A brass strip welded along its length to an iron strip

The third law of thermodynamics has to do with?

Absolute zero

The high specific heat capacity of water has great importance in?

All of the above 1. Climates 2. Cooling systems 3. Ocean currents

At absolute zero, a substance has?

All of the above 1. No more energy to give up 2. Absolutely no molecular motion 3. No volume

To say that water has a high specific heat capacity is to say that water?

All of the above 1. Requires a lot of energy in order to increase in temperature 2. Gives off a lot of energy in cooling 3. Has a lot of "thermal inertia"

What is absolute temperature?

All particles inside a substance have lost their energy Example) The pressure of a gas is due to the multiple collisions of its molecules within the walls of the container. A decrease in the gas temperature reduces the average speed of these molecules, consequently the collisions with the walls becomes less and less frequent resulting in a decrease in the gas pressure. When the absolute zero is reached the molecules are practically motionless and the pressure is zero.

What is translational motion?

All points inside an object move in a parallel path in respect to each other

Pour a liter of 40 degrees C water into a liter of 20 degrees C water and the finale temperature of the two liters becomes?

At or about 30 degrees C

The thermal energy of a substance mostly relates to the?

Average translational kinetic energy and potential energy of particles

What is the expansion of metal?

Bimetallic strip (brass and iron welded together). When the strip is heated, brass expands more than iron. When cooled, brass contracts more than iron. Due to this behavior, the strip bends.

Absolute zero corresponds to a temperature of?

Both 1. -273 degrees C 2. zero degrees K -At absolute zero, a substance has no more energy to give up. 0 K =-273 degrees C

The temperature of boiling water is?

Both 1. 100 degrees C 2. 212 degrees F

The temperature of melting ice is?

Both 1. 32 degrees F 2. zero degrees C

The density of water at 4 degrees C will slightly decrease when it is?

Both 1. Warmed 2. Cooled

Thermal energy is normally measured in units of?

Both of the above 1. Calories 2. Joules - 1 calorie=4.19 Joules

Water at 4 degrees C will expand when it is slightly?

Both of the above 1. Cooled 2. Warmed

How do you convert Fahrenheit to Celsius?

C=5/9(F-32) -Remember your order of operations

What is a calorie?

Calorie is defined as the amount of heat needed to raise the temperature of 1 gram of water by 1 Celsius degree. 4.19 joules=1 calorie -So 4.19 joules of heat will change that temperature of 1 gram of water by 1 Celsius degree

Hot steam that issues from a pressure cooker expands and?

Can cause severe burns

On which temperature scale is 0 degrees the freezing point of water?

Celsius

What is an example of the first law of thermodynamics?

Consider the heating of an inflated balloon. As energy is added to the system (the balloon and the air inside), the temperature increases so some of the heat goes into the internal energy of the air. However, the balloon also expands and some of the energy goes into the work of expanding the balloon.

When a sample of 0 degrees C of water is heated, it first?

Contracts -Ice water contracts due to the melting of microscopic slush crystals. Water continues to contract until it reaches a temperature of 4 degrees C. With further increase in temperature beyond 4 degrees C, water then expands

Aluminum has a specific heat capacity more than twice of that of copper. If equal amounts of heat are given to equal masses of aluminum and copper, the metal that more rapidly increases in temperature is?

Copper

When a sample of 4 degrees C water is cooled, it?

Expands

A metal ring has a gap in it, like the letter C. The ring expands when it is heated. Interestingly, the gap?

Expands also, as much as if metal filled the gap

The usefulness of a bimetallic strip is due to differences in?

Expansions of metals

How do you convert Celsius to Fahrenheit?

F=9/5C+32

Anette heats a metal ring that has the same inner diameter as the diameter of the metal ball. When the ring is hot, the room-temperature ball?

Fits into the hole with more room to spare -When the ring is heated, ALL parts expand

The process of convention occurs in?

Fluids

What happens if there is a change in temperature for heat capacity?

For a change in temperature other than 1 degree C, the heat added (positive) or taken (negative) from the object is expressed as: Heat=(heat capacity of the object) x (final temperature - initial temperature)

When a hot cup is filled with cold water, the direction of heat flow is?

From cup to the water -The second law of thermodynamics tells us that the direction of unassisted heat flow is from hot to cold (If assisted with energy input, as with an air conditioner for example, then heat can flow from cold to hot.)

The second law of thermodynamics tells us that the direction of heat flow is normally?

From hot to cold

When you touch a hot penny in sunlight with your finger, energy flows?

From the penny to your finger

When you touch a piece of ice with your finger, energy flows?

From your finger to the ice

What is the first law of thermodynamics (movement of heat)?

Heat added to a closed system goes into the internal energy of the system and/or into doing work. More specifically, heat added=increase internal energy + external work done by the system (energy can not be created or destroyed)

What is the second law of thermodynamics?

Heat flows spontaneously from a substance at a higher temperature to a substance at a lower temperature and can not flow spontaneously in the reverse direction.

What is heat?

Heat is energy in transit, measure in units of energy-joules or calories -Quantity of heat always has water in the question

What is heat transfer by conduction?

Heat is transferred from a higher temperature object's molecules/atoms to a lower temperature object's molecules/atoms by means of thermal contact

Compared to a giant iceberg, a hot cup of coffee has?

Higher temperature, but less thermal energy

What is an example of the second law of thermodynamics?

Ice cream melts when left out on a warm day. A cold can of soda warms up on a hot day at a picnic. Ice cream and soda never become colder when left in a hot environment, so heat always flows spontaneously from hot to cold, and never from cold to hot.

When a volume of air is compressed, its temperature?

Increases

When work is done ON a system, compressing air in a tire pump for example, the temperature of the system?

Increases -In accord with the first law of thermodynamics, work input increase the energy of the system

The same quantity of heat is added to different amounts of water in two equal-size containers. The temperature of the smaller amount of water?

Increases more

Your toes feel warmer on a tug than on a tile floor because the rug?

Is a better insulator than tile

What is absolute zero or zero K?

Is lowest limit of temperature at -273 degrees C. Pressure and volume are zero -Atoms and molecules have lost all available kinetic energy and substance at this temperature cannot get any colder

(a) During the day, the sun warms the land more rapidly than the water. This is because the land, which is mostly rocks, has a lower specific heat than the water. The warm land heats the air above it, which becomes less dense and rises. Cooler air from over the water flows into take its place, producing a "sea breeze". (b) At night, the land cools off more rapidly than the water-again because of its lower specific heat. Now it is the air above the relatively warm water that rises and it replaced by the cooler air from over the land, producing a "land breeze". Which has the higher specific heat, water or land?

Water -A substance with small temperature changes for large heat changes has a high specific heat capacity. Water takes much longer to heat up in the sunshine than does land. This difference is a major influence on climate.

What is the expansion of water?

Water expands when it turns to ice. Ice has open-structured crystals resulting from strong bonds at certain angles that increase its volume. THIS MAKES ICE LESS DENSE THAN WATER.

Why is perceiving temperature through touch unreliable?

We can perceive temperature by touch. However, this temperature sense is somewhat unreliable, and its range is too limited to be useful for scientific purposes. -It isn't useful because it really matters the original temperature of your hand

What is heat capacity?

We define heat capacity as the heat added to a mass of the substance to increase its temperature by (1 degree C), also defined as: Heat capacity=mass x specific heat capacity

Why does this behavior have significant consequences for the ecology of lakes in northern latitudes?

When the temperatures drop in the winter the surface waters of a lake cool first and sink, allowing warmer water to rise to the surface to be cooled in turn. Eventually, a lake can fill with water at 4 degrees C. Further drops in temperature result in cooler, less dense water near the surface, where it floats until it freezes. Thus lakes freeze on the top surface first, with the bottom surface staying relatively warm at about 4 degrees C. In addition, the ice and snow on top of a lake act as thermal insulation, slowing the continued growth of ice.

What is the water and ice application?

With the cooling of water in the winter the water becomes more dense and sinks. It will continue to sink until the entire pond is 4 degrees C. With the furthering cooling of water at the surface water floats on top and can freeze. Ice formation temperatures lower than 4 degrees C can extend down into the pond.

In your room is a table, chair, and you. Which of these has a temperature normally greater than the temperature of the air in the room?

You