Energy And Heating Flashcards
What are good conductors ?
Copper in wires of plugs
Steel of a bell
Metals
What is a conductor?
Material that allows thermal energy to be transmitted through it easily
How do metals conduct energy from fire?
When metal rod is put into a fire the energy from fire makes the ions in the rod vibrate faster
Since ions are close together in solids this increases vibration meaning the collide more frequently
Energy is passed through the metals in these collisions, transmitting the energy
More frequent collisions increase rate if transfer
What is an insulator
A material that will not allow easy flow of energy
Why is a metal seat worse than a cushion chair?
A metal seat conducts more energy away since its a conductor making the individual feel cold but a cushion would not allow easy energy transfer as it is an insulater
What is thermal conductivity?
Measure of how well a material conducts energy when heated
How can you test thermal conductivity of materials?
A fan of rod with different materials can be heated at one end at the same time
What rod becomes hottest first is the best conducted
Use a tripod stand and a Bunsen burner
What is the method to test different insulation materials?
1)Place small beaker into a large beaker
2)Fill small beaker with hot water from kettle
3)Put cardboard in top of large beaker with a whole for a thermometer
4)Record initial temp and start stopwatch
5)Record temp ever 2 mins for 20 mins
7)Repeat steps with a different material
What is the method to test different insulation materials thickness?
1)Wrap a sheet of paper around a 100ml beaker
2)Fill neaker with hot water from kettle
3)Put cardboard on top of beaker with a whole for a thermometer
4)Record initial temp and start the stopwatch
6)Record temp every 2 mins for 20 mins
7)Repeat steps adding more layers of newspaper each time until 10 layers
What is temperature?
Measure of the amount of kinetic energy in particles
What happens when materials are heated?
They gain kinetic energy
What does the amount of energy needed to change temp depend on?
-Mass of material
-Substance of material
-Desired temp change
What is specific heat capacity?
Amount of energy needed to raise the temp of a 1kg substance by 1°C
What is the method to measure specific heat capacity of a material?
1)Place the immersion heater into the central hole at the top of the block
2)Place the thermometer into the smaller hole and put drops of oil into the hole to make sure the thermometer is surrounded by hot material
3)Fully insulate the block with cotton wool
4)Record temp of block
5Connect heater to power supply and turn off after 10 minutes
6)After 10 minutes temp will still rise with heated off and begin to cool
7)Record highest temp it goes and calculate specific heat capacity
