Physics Chapter 15

*decreases* because all of the metal in the entire piece of metal will go through thermal contraction, making the entire ring larger including the gap proportionally Because the entire thing, including the hole is getting colder, and contracting to get smaller.

As a piece of metal with a hole in it cools, the diameter of the hole decreases. increases. remains the same.

*decreases* When the temperature of water is below 4° Celsius it becomes less dense the more you cool it.

Consider a sample of ice at 0 degrees C. If the temperature is decreased, the volume of the ice decreases. increases. stays the same.

*-low specific heat capacity* the specific heat capacity of any substance is defined as the quantity of heat required to change the temperature of a unit mass of the substance 1 degree.

Does a substance that heats up quickly have a high or a low specific heat capacity? -high specific heat capacity -low specific heat capacity

*4°C* above 4C it begins to go through thermal expansion, and gai density. any where below 4C is start to produce crystalline structures making is more dense.

Water is most dense at _______. 0°C 100°C 4°C less than 0°C

*temperature to an object with a lower temperature.* Heats transfer generally deals with the flow of heat energy from high temperature to lower temperature substances.

Heat energy travels from an object with a high -internal energy to an object with a lower internal energy. -temperature to an object with a lower temperature. -Both of these, for they say essentially say the same thing. -None of the above choices are true.

*less than that of plants* the specific heat capacity of any substance is defined as the quantity of heat required to change the temperature of a unit mass of the substance 1 degree. PLants likely have a higher heat capacity, because they contain a large amount of water. And water has a very high heat capacity.

Hot sand cools off faster at night than do plants and vegetation. This indicates that the specific heat capacity for sand is _______. likely the same as that of plants unrelated to rate of cooling more than that of plants less than that of plants

*is made of open-structured, hexagonal crystals.* In an in a solid form, the hydrogen bonds of waters molecules adjust to hold the negatively charged oxygen atoms apart from each other, which gives the ice more density

Ice has a lower density than water because ice molecules are more compact in the solid state. is made of open-structured, hexagonal crystals. sinks. density decreases with decreasing temperature. molecules vibrate at lower rates than water molecules.

*surface of bodies of water.* the cold comes from the air above the lake, and starts freezing the water from the surface. ice is less dense than water. hence it floats.

Ice tends to form first at the bottom of bodies of water. surface of bodies of water. surface or bottom depending on the water depth.

*a low specific heat* the specific heat capacity of any substance is defined as the quantity of heat required to change the temperature of a unit mass of the substance 1 degree.

If a certain material heats up quickly and cools down quickly, the material has _______. no specific heat to speak of something besides specific heat that is different a low specific heat a high specific heat

*no* energy may be spread around the water among several different kinds of energy

In a glass of water at room temperature, do all the molecules have the same speed? yes no

*Absolute zero*

The lowest possible temperature that a substance may have--the temperature at which molecules of the substance have their minimum kinetic energy.

*high specific heat.* since islands have water around them, during hot period the waters is able to absorb large amount of heat due to its high specific heat, and when its cool it warms the island with the heat it absorbed.

The moderate temperatures of islands throughout the world has much to do with water's high evaporation rate. absorption of solar energy. vast supply of internal energy. high specific heat. poor conductivity.

Specific heat capacity

The quantity of heat per unit mass required to raise the temperature of a substance by 1 Celsius degree.

*vast number of open spaces in the hexagonal ice crystals.* Archimedes' principle is An immersed body is buoyed up by a force equal to the weight of the fluid it displaces. The volume of an object determines how much fluid it displaces

When ice floats in water, a small part of it extends above the surface. Interestingly enough, the volume of ice that extends above the surface is equal to the volume of the vast number of open spaces in the hexagonal ice crystals. water the ice displaces. both of these neither of these

*also increases* due to thermal expantion, the srip gets larger as a whole, including its length.

When the temperature of a strip of iron is increased, the length of the strip _______. also increases decreases in width as it gets longer may increase or decrease decreases

*a net contraction* Because ice cold water is in a state of expansion, because it is forming less dense molecular structures. as it warms up these structures break down. and the H2O molecules get closer together

When the temperature of ice-cold water is increased slightly, does it undergo a net expansion or a net contraction? a net contraction a net expansion

water expands when freezing.* When the temperature of water is below 4° Celsius it becomes less dense the more you cool it. The expansion of the frozen water in the bottle if it is fill all the way up, will cause the bottle to burst, because it needs to take up more space then the bottle can provide.

When you put a bottle of water in the freezer, why is it important to make sure its not completely full?

*from your finger to the ice.* The direction of spontaneous energy transfer is always form a warmer object to a cooler one

When you touch a cold piece of ice with your finger, energy flows from your finger to the ice. actually, both ways. from the ice to your finger.

*an increase of 1 °C is larger*

Which is greater-an increase in temperature of 1 Celsius degree or an increase of 1 Fahrenheit degree? an increase of 1 °F is larger an increase of 1 °C is larger The same.

*270 K* T(°C) = T(K) - 273.15

Which of these cites the lowest temperature? -32°F -270 K -273 K -0° C

*silver* silver has a lower specific heat capacity the specific heat capacity of any substance is defined as the quantity of heat required to change the temperature of a unit mass of the substance 1 degree.

Which warms up faster when heat is applied - iron or silver? silver iron

Temperature

A measure of the average translational kinetic energy per molecule in a substance, measured in degrees Celsius or Fahrenheit or in kelvins (K).

*sometimes*

Can a sample of water possibly have the same volume after being warmed by several Celsius degrees? always never sometimes

*higher temperature, but less internal energy.* The coffee has a higher temperature, because temperature is the directly related to the average kinetic energy (molecules that are in motion). But since the coffee is hot it doesn't mean that that has more energy than the iceberg. The iceberg, is colder which means less KE, However it overall internal energy has MUCH MORE potential energy. PE is also calculated into internal energy. Since it has so many more molecules, even know there frozen and not moving much. They all have potential energy. Which adds to its overall energy.

Compared to a giant iceberg, a hot cup of coffee has higher temperature, but less internal energy. a greater specific heat and more internal energy. more internal energy and higher temperature. none of these

* water expands when freezing.* When the temperature of water is below 4° Celsius it becomes less dense the more you cool it. The expansion of the frozen water in the pipes will break them

During a very cold winter, water pipes sometimes burst. The reason for this is the thawing process releases pressure on the pipes. the ground contracts when colder, pulling pipes apart. water contracts when freezing. water expands when freezing. none of these

It will cause the molecules in the inner glass to expand and have less of a grip on the other glass, allowing them to unstick.

If two nested drinking glasses have stuck together, you can put some ice in the inner one to take them apart. Why does that help?

*smaller than measured.* Because brass contracts in the cold, it would cause the entire length of the tape measure to be shorter.

If you measure a plot of land with a brass tape on a cold day, the actual amount of land you have will be larger than measured. the same. smaller than measured.

*less than 30 degrees C.* heat lost by iron = heat gained by water T is final temperature They both have to equal the same temperature by the end of the heat transfer.

Place a kilogram block of iron at 40 degrees C into a kilogram of water at 20 degrees C and the final temperature of the two becomes at or about 30 degrees C. less than 30 degrees C. more than 30 degrees C.

*The gap will become wider.* because the all of the metal in the entire ring will go through thermal expansion, making the entire ring larger including the gap proportionally

Suppose that you cut a small gap in a metal ring. If you were to heat the ring, would the gap become wider or narrower? The gap will become wider. The gap will become narrower. The gap will stay the same.

Heat

The energy that flows from a substance of higher temperature to a substance of lower temperature, commonly measured in calories or joules.

Internal energy

The total of all molecular energies, kinetic plus potential, that are internal to a substance.

*Heat* The energy that flows from a substance of higher temperature to a substance of lower temperature, *Temperature* A measure of the average translational kinetic energy per molecule in a substance,

What is the difference between temperature and heat?

*larger.* because all of the metal in the entire ring will go through thermal expansion, making the entire ring larger including the gap proportionally

When an iron ring is heated, the hole becomes smaller. larger. neither smaller nor larger. either smaller or larger, depending on the ring thickness.

*ice water.* When the temperature of water is below 4° Celsius it becomes less dense the more you cool it. So the ice water, is water that is beginning to expand at certain parts. If you heat it, all the places that it expanded will contract.

Which of the following contracts when the temperature is increased? Equal volumes of wood. helium. iron. ice water. None of the above contract when heated.

*Water* the specific heat capacity of any substance is defined as the quantity of heat required to change the temperature of a unit mass of the substance 1 degree.

Which of these has the highest specific heat capacity? Soil Water Silver Iron

Specific heat capacity is the amount of energy required to increase the temperature of an object or substance by 1oK. The rate at which something cools is proportional to the difference in temperature between the object and its surroundings. Consequently, neither has any relation to the other.

low. Since it does not store a lot of heat. If the specific heat is high(water), then the substance stores a lot of heat and it takes longer to lose the heat and change the temperature.