Download Temperature - Peach County Schools

What is Thermal
Energy?
Particles of matter are in constant motion. This
motion relates directly to the state of matter of the
object (solids, liquids, or gases).
Temperature affects how fast these particles
move. The higher the temperature the faster the
particles move. Moving particles possess kinetic
energy.
Temperature is defined at the average kinetic
energy of the particles of an object.
Thermal Energy is the sum total of all of the
energy of the particles of an object.
Thermal energy and temperature are related
though DIFFERENT.
Temperature is the average kinetic energy of the
particles of an object.
Thermal energy is the total amount of energy of
the particles of an object.
A bathtub full of water at 100oF has more thermal
energy than a thimble of water at 100oF. The
temperature is the same but the total amount of
energy is different. The bathtub has more energy.
What is heat?
Heat is thermal energy that flows from
something at a higher temperature to
something at a lower temperature.
What is specific heat?
Specific heat is a property of matter which
determines how readily a material is to absorb
heat and change temperature.
Specific Heat is defined as the amount of heat
energy needed to raise the temperature of 1
kg of a substance by 1 oC or 1 K.
Did you notice that water has a very high specific
heat, whereas iron has a low specific heat?
Water requires a lot of heat energy to raise its
temperature.
Transferring Thermal Energy
How is Thermal Energy Transferred? YOU MUST
KNOW THIS!!!!!
Conduction – direct contact
Convection – through a fluid
Radiation – by electromagnetic waves
What is heat transfer by conduction?
Heat transfers as particles of an object increase
their collisions as heated. These collisions
transfer the heat energy through the object by
colliding with adjacent particles.
What is heat transfer by convection?
Heat is transferred through a substance through
currents. This occurs in fluids (liquids AND gases)
Convection currents are caused by heating of a
liquid or gas, the liquid or gas rises, then cools
and falls. This occurs in the mantle of the earth
And in the atmosphere.
Most of our weather patterns are the result of
convection currents in the atmosphere.
What is heat transfer by radiation?
Radiation is heat transfer by electromagnetic
waves. These wave may pass through all states
of matter and also through NO matter – such as
the vacuum of space.
This energy is often called radiant energy.
Radiant energy from the sun travels through the
vacuum of until it reaches the earth.
How is heat flow controlled?
Insulators – a material which does not allow heat
to pass through it easily. Some animals have
good insulation to
survive severe winters.
Buildings and houses are insulated so that heat
does not pass out of (winter time) and into
(summer time).
What are some other uses of insulation?
Conductors- materials that easily
transfers thermal energy (heat).
• Metals- gold and copper, iron and
steel
Using heat – How do we use heat in our lives?
Forced-Air Systems – a fuel is burned in a
furnace and a fan circulates the heat in the house
Radiator Systems – closed metal containers that
contain hot water or steam. The thermal heat is
transferred to the air and circulated by convection
currents.
Electric radiators – heat metal coils which transfer
the thermal heat to the surrounding air.
Using heat to do work – the internal combustion engine
Automobile engines are usually four-stroke
engines since each four-stroke cycle converts
chemical/thermal energy to mechanical energy.
Refrigerators, air conditioners, and heat pumps –
how do they work?
A coolant is circulated through pipes by a
compressor. When the pipes get small and
narrow the coolant compresses and changes to a
liquid giving off heat energy. When the pipes get
larger, the coolant changes from a liquid to a gas
(evaporates) causing the area to absorb heat and
get cooler