Thermal Physics Flashcards
What is an assumption of energy transfer?
Assume there is no transfer of energy to or from the surroundings.
What is the gravitational potential energy equation?
G.P.E. = mgh
What is the electrical energy equation in a solid?
E=IVt or Q=IVt
What is the electrical energy equation in a liquid?
Q=mcT (liquid) + mcT (solid)
What is specific latent heat?
The amount of energy required to change the state of a substance without a change in temperature.
What does fusion mean in relation to latent heat?
Melting.
What does vaporisation mean in relation to latent heat?
The change of liquid to gas.
What is sublimation?
Solid to gas.
What is deposition?
Gas to solid.
What is the equation that links the changing of temperature and state?
Q = mcT + ml
How do you measure continuous flow?
- Take 2 sets of readings.
- Switch on the heater, let liquid flow at constant temp.
- Adjust the flow rate and energy.
- Record the energy supplied, mass of liquid and temperature in and out.
What happens as more energy is transferred by heating? (Specific heat capacity)
There is a greater increase in temperature.
What happens when the mass is smaller? (Specific heat capacity)
A greater increase in temperature.
What is specific heat capacity measured in?
Joules per kilogram.
What affects the temperature in specific heat capacity?
The material.
What is specific heat capacity?
The amount of energy required to raise the temperature of a 1kg substance by 1K without a change in state.
What equation is used to measure an increase in temperature?
Q = mcT
How would two objects be in thermal equilibrium?
Both objects must be at the same temperature.
What is the equation for energy transfer when objects are in thermal equilibrium?
-Q = mcT
What happens to energy gained in thermal equilibrium?
Energy gained = energy transferred.
What happens to kinetic energy when energy is transferred by work?
Kinetic energy increases.
What happens to internal energy when energy is transferred by work?
Internal energy increases.
What happens to potential energy when energy is transferred by work?
There is no potential energy.
What does a change in internal energy equal?
Change in internal energy = energy transfer due to heating + (work done ON)
OR
Change in internal energy = energy transfer due to heating - (work done BY)
