PHY-ENV-101: Energy, Waves & Signals
Uncovered
What does temperature measure? - It measures how hot something is.
What is the unit used for temperature? - The units are: Degrees Celsius, Kelvin or
Fahrenheit.
What is heat a measurement of? - A measurement of energy.
What unit is used for heat? - It is a measurement of energy on an absolute scale, and is always
measured in joules.
What is a thermogram? - An image taken by a thermal imaging camera which can detect the
temperature of different parts of the scene. Temperature can be represented by a range of colours
in a thermogram. Hottest areas appear white/yellow/red, coldest areas appear black/dark
blue/purple.
What does it mean if an object's temperature rises? - It is taking in energy.
What does it mean if an object's temperature falls? - It is giving out heat energy.
What happens if an object's temperature is a higher temperature than another? - The energy will
flow from the hotter region to the cooler region and vice versa.
How does the rate of cooling change depending on the original temperature of an object? - The
higher the temperature of an object, the quicker it will cool, as the temperature falls, it will cool
down at a slower rate.
What does the amount of energy needed to raise an object's temperature rely on? - The mass of
the object, the change in temperature required and the material of the object.
How can you calculate the total energy supplied? - Energy supplied per second x Number of
seconds = Total energy supplied.
, What is meant by specific heat capacity? - It is the energy needed to raise the temperature of 1kg
of material by 1C. Different materials required different amounts of energy.
How can you calculate specific heat capacity? - Energy ÷ (Mass x Temperature Change) =
Specific Heat Capacity
Why doesn't the temperature of a material change when it's changing state (boiling, melting,
freezing)? - Because the energy supplied is being used up to break intermolecular bonds of the
substance which explains why the temperature doesn't change.
What is meant by specific latent heat? - The amount of energy needed to melt or boil 1kg of a
material.
What does the specific latent of a substance depend on? - It depends on:
The material of the object.
The state (solid, liquid or gas.)
How can you calculate specific latent heat? - Energy ÷ Mass = Specific Latent Heat
What are conductors? - They are materials that allow energy to flow through them
quickly.
What are insulators? - They are materials that allow energy to flow through them much more
slowly. Most non-metals are insulators.
Why are curtains good insulators? - They are good because they trap a layer of air between them
and the window which reduces energy loss.
Give examples of different methods of insulation. - Fiberglass, roof insulation, reflective foil on
walls, foam cavity wall insulation, double glazing and draught excluders.
Why is it important to try and slow down the rate of which energy escapes? - Because:
Energy costs money.
Most houses use fossil fuels as their energy supply will eventually run out.
Uncovered
What does temperature measure? - It measures how hot something is.
What is the unit used for temperature? - The units are: Degrees Celsius, Kelvin or
Fahrenheit.
What is heat a measurement of? - A measurement of energy.
What unit is used for heat? - It is a measurement of energy on an absolute scale, and is always
measured in joules.
What is a thermogram? - An image taken by a thermal imaging camera which can detect the
temperature of different parts of the scene. Temperature can be represented by a range of colours
in a thermogram. Hottest areas appear white/yellow/red, coldest areas appear black/dark
blue/purple.
What does it mean if an object's temperature rises? - It is taking in energy.
What does it mean if an object's temperature falls? - It is giving out heat energy.
What happens if an object's temperature is a higher temperature than another? - The energy will
flow from the hotter region to the cooler region and vice versa.
How does the rate of cooling change depending on the original temperature of an object? - The
higher the temperature of an object, the quicker it will cool, as the temperature falls, it will cool
down at a slower rate.
What does the amount of energy needed to raise an object's temperature rely on? - The mass of
the object, the change in temperature required and the material of the object.
How can you calculate the total energy supplied? - Energy supplied per second x Number of
seconds = Total energy supplied.
, What is meant by specific heat capacity? - It is the energy needed to raise the temperature of 1kg
of material by 1C. Different materials required different amounts of energy.
How can you calculate specific heat capacity? - Energy ÷ (Mass x Temperature Change) =
Specific Heat Capacity
Why doesn't the temperature of a material change when it's changing state (boiling, melting,
freezing)? - Because the energy supplied is being used up to break intermolecular bonds of the
substance which explains why the temperature doesn't change.
What is meant by specific latent heat? - The amount of energy needed to melt or boil 1kg of a
material.
What does the specific latent of a substance depend on? - It depends on:
The material of the object.
The state (solid, liquid or gas.)
How can you calculate specific latent heat? - Energy ÷ Mass = Specific Latent Heat
What are conductors? - They are materials that allow energy to flow through them
quickly.
What are insulators? - They are materials that allow energy to flow through them much more
slowly. Most non-metals are insulators.
Why are curtains good insulators? - They are good because they trap a layer of air between them
and the window which reduces energy loss.
Give examples of different methods of insulation. - Fiberglass, roof insulation, reflective foil on
walls, foam cavity wall insulation, double glazing and draught excluders.
Why is it important to try and slow down the rate of which energy escapes? - Because:
Energy costs money.
Most houses use fossil fuels as their energy supply will eventually run out.
