What Is Heat?What Is Heat?
• Heat is a form of energy. It affects the Heat is a form of energy. It affects the movement of molecules or particles movement of molecules or particles in matter.in matter.
• Heat energy is measured in units Heat energy is measured in units called calories. Adding calories of called calories. Adding calories of heat to matter will raise the heat to matter will raise the temperature of it.temperature of it.
Particles In MatterParticles In Matter• All matter is made up of All matter is made up of
tiny moving particles.tiny moving particles.• The more energy matter The more energy matter
has, the faster the has, the faster the particles move and the particles move and the matter becomes warmer.matter becomes warmer.
• The slower the particles The slower the particles move, the less energy move, the less energy matter has, and the matter has, and the cooler the matter is.cooler the matter is.
Particles moving faster
Particles moving slower
Heat and TemperatureHeat and Temperature
• Temperature is a measure of Temperature is a measure of the speed of particles.the speed of particles.
• Heat and temperature ARE Heat and temperature ARE NOT the same things. Heat is NOT the same things. Heat is energy that causes the energy that causes the particles to move at different particles to move at different speeds, and temperature speeds, and temperature just measures the speed of just measures the speed of the moving particles.the moving particles.
Measuring Measuring TemperatureTemperature
• Temperature is Temperature is measured in measured in degrees Celsius degrees Celsius ((ooC)C)
Pleasant Summer Pleasant Summer Day- 27Day- 27ooCCIce- 0Ice- 0ooCC
Boiling water, or Boiling water, or coffee- 100coffee- 100ooCC
Which Has More Which Has More Heat??Heat??
• The bathtub has The bathtub has more heat. It has more heat. It has more particles more particles than the teacup, than the teacup, therefore it has therefore it has more heat.more heat.
Boiling water in a bathtub
Boiling cup of soup
Same Temp.
ConductionConduction• Conduction is the Conduction is the
way heat energy way heat energy moves through a moves through a solid.solid.
HEAT SOURCE
•The particles of The particles of matter in the heat matter in the heat source hit the source hit the particles of matter in particles of matter in the spoon. The the spoon. The particles in the spoon particles in the spoon that were hit begin to that were hit begin to vibrate faster. These vibrate faster. These particles hit other particles hit other particles in the spoon, particles in the spoon, causing the other causing the other particles to vibrate particles to vibrate faster and pass heat faster and pass heat along the spoon.along the spoon.
Conductors and Conductors and insulatorsinsulators
• The molecules are close together
• Heat energy can easily move through them
• The molecules are spaced far apart
• Heat energy CANNOT move easily through them.
CONDUCTORS INSULATORS
convectionconvection•Convection is the way heat energy moves through a liquid or a gas.
•The fireplace heats the air around it. Warm air is less dense, or lighter than cool air, so it rises to the ceiling. Cool air drops to the floor since it is heavier, to replace the warm air that rose. In this way, a room is heated by convection.
Heat From Sunlight• The sun gives off
rays other than just light. These invisible rays transfer heat.
• The movement of heat energy in waves is called radiation.
Light energy
Other forms of energy
The Greenhouse Effect
• Waves of energy from the sun travel through the glass roof of the greenhouse. When the waves strike matter inside, they change to heat. Heat can’t escape back out through the glass, so it gets trapped inside.
Chapter concepts• Heat is a form of energy; it is the
vibration of particles in matter. • Temperature is a measure of the speed
of particles.• Heat energy is transmitted through
solids by conduction.• Heat energy is transmitted through
liquids and gases by convection.• Heat energy that moves in waves is
called radiation.
Important VocabularyHeat~
Calorie~
Temperature~Degrees Celsius~
Conduction~
Insulator~
Convection~
Radiation~
A form of energy; actually the vibration of particlesThe unit heat energy is measured in
A measure of the speed of particles
Units temperature can be measured in
How heat energy moves through a solidMaterial that doesn’t allow much heat
energy to pass through
How heat energy moves through a liquid or gas
The movement of heat energy in waves
Science words• Heat energy moves in different ways
through different kinds of matter. The way heat energy moves through a solid is called ________.
• Heat energy doesn’t move at the same speed through all kinds of solids. Heat energy can easily move through a type of solid called a/an _________.
• Heat energy can’t move easily through another type of solid called a/an ________.
• The way heat energy moves through liquids and gases is called __________.
• Heat energy also comes from waves of energy from the sun. The movement of heat energy in waves is called _________.
Word Bank
convection
conduction
insulator
conductor
radiation
conduction
conductor
insulator
convection
radiation
Which has more heat?
• The soup in each bowl has the The soup in each bowl has the same same temperature. Which bowl of soup temperature. Which bowl of soup contains more contains more heatheat??
Insulator vs Conductor
• Which are insulators? Which are insulators?
What is the What is the picture picture remaining?remaining?
CONDUCTORCONDUCTOR