Thermal energy Flashcards
Kinetic energy eqaution
E = 1 mv sqaured
2
What does theoretical mean
Based on ideas
What does empirical mean
Based on proof
What did we see when we looked through the microscope at the smoke particles
When we looked through the microscope we saw tiny white smoke particles moving in random directions because they were bouncing off of the air particles the reason they move in this motion is because they have more impact on one side of the atom and the other causing a resultant force where the more impacted the smoke moves in that direction which changes randomly so there is a zigzag motion
What is the boiling point and melting point of argon oxygen and water
Boiling. Melting
Argon. -185. -189
Oxygen -183. -218
Water. 100. 0
Definition of temperature
It is the degree of hotness of an object and it can be measured by thermometer temperature can be expressed by Celsius Fahrenheit or kelvin scale
Definition of heat
It is the energy which travels from high temperature to low temperature in a matter it is also called thermal or internal energy it is measured in joules
What is Brownian motion
Random movement of particles of liquids or gases
What is the proof of kinetic theory
Is Brownian motion less smoke particles move in random direction is hitting other particles as well as that when you heat atoms up the pressure builds causing the atoms to move quicker therefore more kinetic energy
Proof of kinetic theory examples
Brownian motion
Particles moving around create pressure less particles high up less pressure expansion of gases in aeroplane
Pumping up a timer
Expansion of a liquid
Expansion of a solid
What is absolute zero
0k or -273 degrees Celsius
How does the expansion of metal happen when heated
It’s a metal is heated the particles inside it gain more kinetic energy which means they move quicker therefore the increase in speed hitting each other more times and therefore expanding the solid
The expansion of liquids
When the liquid is heated the molecules have more energy and move more vigourously the movement of the molecules overcome the forces of attraction between the molecules allowing them to move freely loss the volume of the liquid increases
The contraction of liquids
Lower temperature in the molecules have less energy and move closer to each other this causes the volume of the liquid to decrease
Can solids expand and contract a lot
Only a small amount because particles are held tightly by inter molecular forces around a fixed position
Can gases expand and contract a lot
Quite large contraction and expansion because atoms held by weaker forces
Can gases expand and contract a lot
Yes large amounts expansion increases pressure in the container because particles move more quickly and hit container with more force contraction reduce pressure in a container because particles move slower and hit container with less force
How does a solid expand
When heated The particles in a solid move around quicker therefore hitting the container and other particles with a bigger force which pushes the particles further apart therefore expanding
Where does conduction occur
In solids or metals
Where does convection occur
Liquids and gases
Where does radiation occur
From any hot object liquid or gas
What is conduction
It is the heat transfer by means of faster pop molecules motion within the material without any shift of the material as a whole if one end of a metal rod is it higher temperature than energy will be transferred towards the colder end because the higher speed particles will collide with the slower ones with a net transfer of energy to the silver ones all metals are good conductors because of delocalised electrons
What is convection
It is heat transferred by the motion of fluids such as air or water when they are heated fluid is cause to move away from the source of heat carrying energy with it convection above a hot surface occurs because hot air expands becomes less dense and rises hot water is less dense than cold water and rises causing convection currents which transfer energy
What is radiation
It is the flow of heat from one place to another by means of electromagnetic waves the colour and shiny Ormat surface changes the amount of radiation omitted and absorbed
