Physics Flashcards
Define atomic mass
The total number of protons and neutrons in the nucleus of an atom
What are isotopes?
Atoms with the same number of protons but a different number of neutrons.
Define atomic number
The number of protons in the nucleus of an atom.
What is latent heat?
The energy required to transform matter from one state to another in Joules per Kg. It is the energy required to break bonds or form them. During this state change there is no change in temperature.
How many Joules are in a calorie?
4.16 Joules
What is specific heat capacity, please draw an equation?
The energy required to raise 1 kg of a substance by 1 C.
Q = C x M x △ T
Q = energy required
C = specific heat capacity
M = Mass
△ T = Temp change
What is the specific heat capacity of water?
4.18 J.g-1.c-1 or 4.18 Kj.Kg-1.C-1
What is the triple point ? and what is the value for water.
The temperature and pressure where all three states of matter can co-exist.
TP of water = 0.01 C at 0.006 atmospheres.
What is critical temperature?
The temperature above which no amount of pressure no matter how great will cause a gas to liquefy.
What is critical pressure?
The minimum amount of pressure required to liquefy a gas at its critical temperature.
What is the critical point and what are the values for water ?
The temperature and pressure above which a substance can only exist in its gaseous phase.
H2O Critc pressure 218 Bar and Crit temp 374C
What is force?
An influence capable of producing a change in the velocity of a mass
What is velocity?
The speed and direction of an objects movement
Newtons first law?
Objects move in a straight line at a constant speed or remain stationary unless a force acts upon it.
Newtons second law?
F = M x A
A force acting on a body produces an acceleration proportional to the force and inversely proportional to the mass.
Define acceleration
The rate of change of velocity with respect to time
What is Newtons third law.
Every action of a force produces an equal and opposite reaction.
What is a newton?
The force required to provide a mass of one kilogram with an acceleration of 1 m.s-2
Define weight
Weight = mass in Kg x acceleration due to gravity m.s-2
Define pressure
Force applied to an object per unit area
P (n.m-2) = F (N)/A (M2)
What is hookes law?
There is a linear relationship between the force applied to a spring and its extension within its elastic limits.
F = -K (spring constant i.e. stiffness) . x (extension)
What is viscosity?
A measure of a fluids resistance to flow. Expressed in Poise (Pa.S) or dyne.sec.cm-2
What are newtonian and non newtonian fluids?
Newtonian fluid: A fluid with a constant viscosity regardless of flow e.g. H2O
Non Newtonian fluids have a change in viscosity with flow e.g. blood as flow increases viscosity decreases.
What is laplaces law?
