Thermal energy and change of state Flashcards
1
Q
Conduction involves
A
Vibrating molecules (solids)
2
Q
Convection involves
A
Moving molecules (liquids)
3
Q
Radiation involves
A
Waves from the EM spectrum especially IR
4
Q
Conduction is reduced by
A
Insulators
5
Q
Convection is reduced by
A
Trapping the liquid or gas in small pockets
6
Q
Radiation is reduced by
A
Shiny, light coloured surfaces
Low surface temperature
7
Q
Conduction is stopped by
A
Vacuum + layer of gas
8
Q
Convection is stopped by
A
Vacuum
9
Q
Radiation is stopped by
A
Nothing
10
Q
Gas
A
- Container shape
- Container volume
- Particles move freely and quickly
11
Q
Liquid
A
- Container shape
- Fixed volume
- Particles have fluid motion within a fixed structure
12
Q
Solid
A
- Fixed shape
- Fixed volume
- Particles vibrate about fixed positions within a fixed structure
13
Q
Solid to liquid
A
Melting
14
Q
Liquid to Gas
A
Boiling or evaporation
15
Q
Gas to liquid
A
Condensation
16
Q
Liquid to solid
A
Freezing
17
Q
Solid to gas
A
Sublimation
18
Q
What is specific heat capacity?
A
the energy required to change the temperature of an object by 1oc per kilogram of mass
19
Q
ΔQ
A
mcΔT
20
Q
How to find the specific heat capacity of a block
A
- measure the mass of the block using a balance
- place the thermometer into the smaller hole and put a couple of drops of water in to make sure it is surrounded
- Place the immersion heater into the other hole
- Set up the circuit in the diagram
- Turn on the power supply and start your timer
- Record the temperature, current and potential difference
- Repeat every 60s for 10 mins
- To calculate energy transferred multiply time, current and potential difference
