physics 1 revision lesson 2 factors affecting cooling and insulating buildings
TRANSCRIPT
Physics 1 Revision
Lesson 2
Factors affecting cooling and Insulating buildings
Factors affecting cooling
As energy increases the probability of
evaporation increases
As pressure increases the probability of
evaporation decreases
The larger the surface area, the faster the rate of cooling.
This is because more of the object is exposed to the outside
Large surface area
Small surface area
The bigger the temperature difference, the faster the rate of cooling
40ºC10ºC
Here the liquid will cool down faster since there is a 30ºC difference
between it’s temperature and the surroundings
40ºC35ºC
Here the liquid will cool down slowly since there is only a 5ºC
difference between it’s temperature and the
surroundings
Heating and Insulating buildings
Good insulators don’t allow heat to travel through them
insulators do not have free electrons
the lower the u value the better a material is at insulating
the amount of heat required to heat something by 1ºC
is called specific heat capacity
Key words and statements
Insulators
U value
Specific heat capacity
Cooling
Surface area
Temperature difference
Evaporation
Condensation
When a gas turns into a liquid because the atoms have lost energy
When temperature decreases due to a loss of energy
The amount of surface exposed to the outside
When a liquid turns into a gas because the atoms have gained energy
The difference between outside and inside temperature
The amount of heat required to raise the temperature of an object by 1ºC
A material with no free electrons and therefore doesn’t allow heat to pass easily through it
A measurement of how much heat is lost through a material. A low u value mans that
less heat is lost
Factors affecting cooling and insulating buildings
Insulators
U value
Specific heat capacity
Cooling
Surface area
Temperature difference
Evaporation
Condensation
When a gas turns into a liquid because the atoms have lost energy
When temperature decreases due to a loss of energy
The amount of surface exposed to the outside
When a liquid turns into a gas because the atoms have gained energy
The difference between outside and inside temperature
The amount of heat required to raise the temperature of an object by 1ºC
A material with no free electrons and therefore doesn’t allow heat to pass easily through it
A measurement of how much heat is lost through a material. A low u value mans that
less heat is lost
Factors affecting cooling and insulating buildings
A small temperature difference…
A large u value means…
The amount of heat needed to heat a substance by 1ºC is called…
A small u value means…
A smaller surface areas causes…
A large temperature difference…
Increased pressure causes decreased rate of evaporation because…
Increased temperature increases rate of evaporation because…
The particles are gaining energy at a faster rate, causing them to turn into a gas and
evaporate more quickly
That a material is a good conductor as more heat can pass through it
Decreases the rate of heat loss
Specific heat capacity
The particles are being squashed together and they require more energy than usual to
evaporate and turn into a gas
That a material is a bad conductor but a good insulator because less heat can pass through it
A decrease in heat loss because there is less area exposed to the outside.
Increases the rate of heat loss
Factors affecting cooling and insulating buildings
A small temperature difference…
A large u value means…
The amount of heat needed to heat a substance by 1ºC is called…
A small u value means…
A smaller surface areas causes…
A large temperature difference…
Increased pressure causes decreased rate of evaporation because…
Increased temperature increases rate of evaporation because…
The particles are gaining energy at a faster rate, causing them to turn into a gas and
evaporate more quickly
That a material is a good conductor as more heat can pass through it
Decreases the rate of heat loss
Specific heat capacity
The particles are being squashed together and they require more energy than usual to
evaporate and turn into a gas
That a material is a bad conductor but a good insulator because less heat can pass through it
A decrease in heat loss because there is less area exposed to the outside.
Increases the rate of heat loss
Factors affecting cooling and insulating buildings