P3 - Thermal physics Flashcards
How do you change degrees C to kelvin?
+ 273
What happens to the particles in a gas when temperature increases?
The average particle speed increases
The average kinetic energy of the particle increases
The distribution curve becomes more spread out
What is a closed system?
what is the total internal energy of a gas?
A system that does not allow for any transfer of matter in or out. For a closed system the total internal energy is constant.
The average kinetic and potential energy’s of all the particles added up
How can the internal energy of a system change?
The internal energy of a system can change by heating it or applying work done to transfer energy to the system(eg changing its shape). In this case the average speed of the particles will increase.
What is the specific heat capacity of a substance?
what does Q, M,C, mean in the SHC equation?
The specific heat capacity of a substance is the amount of energy needed to raise the temperature of 1kg of the substance by 1 kelvin.
Q is energy change in J
M is mass
C is specific heat capacity
What happens to an objects internal, kinetic energy and temperature when it changes state?
Its internal energy changes as its potential energy increase, but its kinetic energy stays the same as its temperature stays the same
What is the specific latent heat of an object?
what does Q and L stand for in the equation?
The specific latent heat of fusion is the quantity of thermal energy needed to be gained or lost to change the state of 1kg of a substance.
Q is the change in energy in J
L is the specific latent heat
What is boyls’s law? (constant temperature)
At a constant temperature the pressure p and volume V of a gas are inversely proportional.
So in an ideal gas the product of pressure and volume will always be the same
What is Charles law? (constant pressure)?
At constant pressure, the volume V of a gas is directly proportional to its absolute temperature T.
When charles law is obeyed the volume divided by time is always constant
What is the pressure law? (constant volume)
The pressure law states that at constant volume, the pressure p of an ideal gas is directly proportional to its absolute temperature T
If the pressure law is obeyed pressure over temperature will always be constant
What is molecular mass? think atoms
Molecular mass is the sum of the masses of all the atoms that make up a single molecule.
What is molar mass?
Molar mass is the mass in grams that the said volume of molecules is. Just a unit of measurement baso
In the ideal gas equation what does P, V, n, R , T mean?
what does BIG N and k mean?
P is pressure V volume n is the number of moles of gas R is the molar gas constant T is the temperature in kelvin
Big N is the number of molecules of gas
k is the Boltzmann constant
What are the assumptions made in kinetic theory? (an ideal gas)
All molecules of the gas are identical
The gas contains a large number of molecules.
The molecules have a negligible volume compared with the volume of the container
The molecules continually move about randomly
Newtoniain mechanics apply ( motion follows newtons laws)
Collisions between molecules themselves or at the walls of a container are perfectly elastic
The molecules move in a straight line between collisions.
The forces that act during collisions last for much less time than the time between collisions.
How do you find the peak to peak voltage of a mains power supply?
times by root 2
double
