Understanding Heat And Temperature Flashcards
How do we measure temperature?
Thermometer
Unit of temperature - degrees Celsius
What is temperature.
Temperature is how hot or cold an object is.
What is heat?
Heat is a measure of the total internal energy of an object.
When a substance is heated the particles vibrate faster and the kinetic energy increases. Temperature is a measure of the average kinetic energy of the particles.
It is measured in Joules
What affects the rate or speed of energy transfer?
The difference in temperature affects the speed of transfer of energy.
What is a Thermogram?
A thermogram is a picture taken by a special camera in which colour is used to represent temperature.
What are the units of temperature.
Degrees Celsius
What is the unit of energy?
Joules
What is meant by ‘change of state’ ?
When a substance changes form between a solid , liquid and gas.
Energy is required to break bonds when changing from solid to liquid or liquid to gas -that is why there is no change in temperature.
Water - ice to water to steam
What is Specific Latent Heat?
Specific Latent Heat is the amount of energy needed to change the state of one Kg of a substance without a change in temperature.
Energy transferred = mass x specific latent heat
The unit is J/ Kg
It depends on the material the object is made from.
Energy is transferred even though there is no change in temperature when substances boil or condense, melt or freeze.
Heat is needed to melt a solid at its melting point.
Heat is needed to boil a liquid at its boiling point.
Does energy transfer always involve a rise or fall in temperature?
NO
The energy may be being used to change the state of a substance
What is Specific Heat Capacity?
The Specific Heat Capacity is the amount of energy needed to change the temperature of one Kg of a substance by 1 degree C
Energy transferred = mass x specific heat capacity x temperature change
The unit of Specific Heat Capacity is
Joule per Kg degree C- J/Kg*C
