AQA A Level PHYSICS PAPER 2
SOLUTIONS GRADE A+ GUARANTEED
Gravitational Field
A region in which an object that has mass experiences a force
Field Lines
Arrows which indicate the direction and relative strength of a field.
Arrows show the way in which a rest mass would experience the force
of attraction.
Equipotentials
Lines drawn to indicate points of equal potential. Cross field lines
at 90 degrees
Newton's Law of Gravitation
Every particle in the universe attracts every other particle with a
force that is directly proportional to the product of their masses
and inversely proportional to the square of the distance between
their centre's
F ~~ Mm/r^2
Gravitational field strength
The force acting on a body per unit mass
Gravitational Potential Energy
Potential energy is the work done in moving an object with mass from
Infinity to that point in the field
E=-gMm/r for radial field E=mg•dh (Scalar)
Absolute Gravitational potential
The absolute gravitational potential at a point is the work done per
unit mass in moving a body from Infinity to that point in the
gravitational field
V=-Gm/r (scalar)
Orbital time period
GMT^2 =4pi^2 •r^3 therefore T^2 prop R^3
orbital velocity
(GM/r)^1/2
escape velocity
(2GM/r)^1/2
Satellites in geosynchronous orbit
T=24hrs
Orbital Radius roughly 36,000km
, Remember the subtle difference between geosynchronous and
geostationary, Which stay above the same point on Earth.
Satellites in a non-geosynchronous/polar orbit
Different, usually smaller T than earth.
Activity
Number of emissions per second measured in Bq
Alternating Current (AC)
A flow of electric charge that continuously changes its direction and
magnitude
Avogadro's Law
equal volumes of gases at the same temperature and pressure contain
equal numbers of molecules
Boltzmann's constant
a physical constant relating the average kinetic energy of particles
in a gas with the temperature of the gas; it is the gas constant R
divided by Avogadro's number (1.38x10^-23 J K^-1)
Boyle's Law
P1V1=P2V2
Brownian motion
The observable random movement of particles such as smoke particles
caused by the high-speed thermal motion of liquid or gas molecules
Capacitance
C=Q/V charge stored per init pd applied across a capacitor unit Farad
Charles' Law
V1/T1=V2/T2
control rods
neutron-absorbing rods that help control the reaction by limiting the
number of free neutrons often boron or cadmium
Coulomb's Law
F=K Qq/r², magnitude of force between two charges
critical mass
The minimum mass of a fissionable isotope that provides the number of
neutrons needed to sustain a chain reaction
Decay constant
Probability of decay of a nucleus per unit time = λ=ln2/T, where T
is half life
Eddy currents
An alternating magnetic flux through an iron core induces EMFs in the
core, which drive Eddy currents; these generate heat in the core and
resulting in energy wastage.
Elastic collision
A collision in which the total Ek is conserved, ie the sum of the Eks
before and after the collision is equal
Electric Potential (V)
SOLUTIONS GRADE A+ GUARANTEED
Gravitational Field
A region in which an object that has mass experiences a force
Field Lines
Arrows which indicate the direction and relative strength of a field.
Arrows show the way in which a rest mass would experience the force
of attraction.
Equipotentials
Lines drawn to indicate points of equal potential. Cross field lines
at 90 degrees
Newton's Law of Gravitation
Every particle in the universe attracts every other particle with a
force that is directly proportional to the product of their masses
and inversely proportional to the square of the distance between
their centre's
F ~~ Mm/r^2
Gravitational field strength
The force acting on a body per unit mass
Gravitational Potential Energy
Potential energy is the work done in moving an object with mass from
Infinity to that point in the field
E=-gMm/r for radial field E=mg•dh (Scalar)
Absolute Gravitational potential
The absolute gravitational potential at a point is the work done per
unit mass in moving a body from Infinity to that point in the
gravitational field
V=-Gm/r (scalar)
Orbital time period
GMT^2 =4pi^2 •r^3 therefore T^2 prop R^3
orbital velocity
(GM/r)^1/2
escape velocity
(2GM/r)^1/2
Satellites in geosynchronous orbit
T=24hrs
Orbital Radius roughly 36,000km
, Remember the subtle difference between geosynchronous and
geostationary, Which stay above the same point on Earth.
Satellites in a non-geosynchronous/polar orbit
Different, usually smaller T than earth.
Activity
Number of emissions per second measured in Bq
Alternating Current (AC)
A flow of electric charge that continuously changes its direction and
magnitude
Avogadro's Law
equal volumes of gases at the same temperature and pressure contain
equal numbers of molecules
Boltzmann's constant
a physical constant relating the average kinetic energy of particles
in a gas with the temperature of the gas; it is the gas constant R
divided by Avogadro's number (1.38x10^-23 J K^-1)
Boyle's Law
P1V1=P2V2
Brownian motion
The observable random movement of particles such as smoke particles
caused by the high-speed thermal motion of liquid or gas molecules
Capacitance
C=Q/V charge stored per init pd applied across a capacitor unit Farad
Charles' Law
V1/T1=V2/T2
control rods
neutron-absorbing rods that help control the reaction by limiting the
number of free neutrons often boron or cadmium
Coulomb's Law
F=K Qq/r², magnitude of force between two charges
critical mass
The minimum mass of a fissionable isotope that provides the number of
neutrons needed to sustain a chain reaction
Decay constant
Probability of decay of a nucleus per unit time = λ=ln2/T, where T
is half life
Eddy currents
An alternating magnetic flux through an iron core induces EMFs in the
core, which drive Eddy currents; these generate heat in the core and
resulting in energy wastage.
Elastic collision
A collision in which the total Ek is conserved, ie the sum of the Eks
before and after the collision is equal
Electric Potential (V)
