Heat is a form of:

Everything in the universe has heat energy! Your BODY, your CAR…even ICE!

Temperature: Temperature is ONLY a

measurement of particle motion.

Temperature measures the average kinetic energy of the molecules of an object or substance.

SUMMARY:HEAT IS ENERGYTEMPERATURE IS A MEASUREMENT OF MOTION

3 Main Temperature Scales

1) Celsius2) Fahrenheit3) Kelvin

What you need to know about the Fahrenheit Temperature Scale

1) Fresh water freezes at 32 degrees Fahrenheit

2) Fresh water boils at 212 degrees Fahrenheit

What you need to know about the Celsius Temperature Scale

1) Fresh water freezes at 0 degrees Celsius

2) Fresh water boils at 100 degrees Celsius

3) It is the most commonly used scale except for in the United States.

What you need to know about the Kelvin Temperature Scale

1) There are NO NEGATIVE NUMBERS

2) Based on absolute zero (all molecule movement has stopped).

3) The size of a Kelvin degree is equal in magnitude (size) to a Celsius degree.

Temperature is measured with thermometers.

There are several types of thermometers.

THERMOMETER TYPES:1) Liquid Thermometer2) Bimetallic strip3) Digital

Liquid ThermometerCan only measure temperatures in a certain range.Uses the expansion of liquid alcohol or mercury (Hg) to indicate changes in temperature.

Bimetallic StripA coil is made using two different metal strips pressed togetherBoth strips expand and contract at different rates as the temperature changesAs the temperature changes, the coil winds and unwinds

DIGITAL THERMOMETERSMeasures temperature by noting the change in current

Changes in temperature also cause electric current to change in a circuit

Heat moves from objects with higher energy to objects with lower energy

HEAT CAN MOVE IN 3 WAYS

1) CONDUCTION2) CONVECTION3) RADIATION

For heat to be transferred by conduction:

objects must be in direct contact with each other—

THEY MUST BE TOUCHING!!!

Convection: Transfer of

energy by the movement of fluids with different temperatures For it to be

fluid, it can be a liquid or a gas!

Radiation: Transfer of energy

by electromagnetic waves

NO DIRECT CONTACT!!!

Does not require a medium to travel!

It is the only way solar heat energy can travel to Earth!

Some objects act as conductors and some act as insulators.

A conductor is a material that transfers heat quickly

An insulator is a material that slows the transfer of heat

Specific Heat Describes how much

energy is required to raise an object’s temperature.

The specific heat value is how much energy is required to raise 1 kg. of a substance by 1 degree Kelvin or Celsius

Denoted by “c” in calculations.

Specific Heat EquationEnergy = (specific heat) x (mass) x

(temperature change)OR

energy = cm t

The Kinetic Theory of Matter explains the behavior of molecules in matter.

It states that all matter is made of constantly moving particles that collide without losing energy.

Kinetic Theory of Matter

When the temperature of a substance is increased, its molecules move faster and usually move farther apart. This is thermal expansion. It occurs in all forms of matter (there are a few exceptions).

Water is an exception – it expands when it is cooling from 4 degrees C to 0 degrees C.

Thermal Expansion

There are four states of matter:

1. Solid State2. Liquid State3. Gas State4. Plasma State

States of Matter

For Solids:• Particles are packed

closely together and are constantly vibrating in place

• Solids have a fixed volume

• Solids have a fixed shape

States of Matter

For Liquids• The attractive

forces between particles are weaker than in a solid

• Particles can slide past each other

• Liquids have a fixed volume.

• Liquids do not have a fixed shape.

States of Matter

For Gases• Particles are farther

apart than in a liquid or solid.

• Attractive forces are weak.

• Gases have no definite shape.

• Gases have no definite volume.

States of Matter

For Plasma• Most common state

of matter in the universe

• Consists of positively and negatively charged particles.

• No definite shape• No definite volume

States of Matter

Changes in the thermal energy of a material can cause it to change from one state to another.

States of Matter

Melting – When thermal energy is added to a solid, the change of a substance from a solid to a liquid is called melting.

Heat of fusion – The amount of energy required to change 1 kg of a substance from a solid to a liquid at its melting point, or when a liquid becomes a solid.

States of Matter

Freezing – Phase change of an object from the liquid phase to the solid phase.

Vaporization – Change of a liquid into a gas.

1. Evaporation-Vaporization that occurs at the surface of a liquid.

2. Boiling – Vaporization occurring throughout the liquid.

States of Matter

Condensation – When a gas changes into a liquid.

States of Matter

To raise indoor air temperature on a cold day, energy must be transferred into a room’s air by a heating system.

Heating system – Any device or process that transfers energy to a substance to raise the temperature of the substance.

Types of Heating Systems: Forced Air

Systems Radiator Systems Electric Heating

Systems

Heating and Work increase thermal energy You can warm your hands by either

placing them near a heat source or rubbing them together

In this example, your hands would be considered to be a system. A system can be a group of objects

you can draw a boundary around to consider certain values about a scenario.

THERE ARE 2 TYPES OF SYSTEMS: OPEN-Thermal energy can flow across

your “boundary” or if work is done across the boundary

CLOSED – Thermal energy is contained within the “boundary” and no outside work is done.

First Law of Thermodynamics

The increase in the thermal energy of a system equals the work done on the system plus the thermal energy transferred to the system

Second Law of Thermodynamics

Energy moves from warmer objects (higher energy) to cooler objects (lower energy)

Cooling System – A device that transfers energy as heat out of an object to lower its temperature.

Cooling Systems use evaporation to transfer energy from their surroundings using a refrigerant

Refrigerant – A substance used in cooling systems that transfers large amounts of energy as it changes state