| Term | Definition |
| linear momentum | the product of
mass and velocity and appreciate the vector
nature of momentum |
| Newtons Second Law of motion | The net force acting on an object is directly proportional to the rate of change of momentum of that object. |
| Impulse of force | Area under a force against time graph (Force * time)
Equal to the change in momentum |
| perfectly elastic collision and an
inelastic collision | Perfectly elastic - Momentum and kinetic energy conserved
Inelastic - only momentum is connserved |
| the principle of conservation of
momentum | Within a closed system, the total momentum in any specific direction remains constant. |
| radian | One radian is the angles subtended at the centre of a circle by an arc of length equal to its radius of the circle. |
| gravitational field strength | The gravitational field strength at a point is the gravitational force exerted per uni mass on a small object placed at that point. |
| Newton’s law of gravitation | Any two point masses attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of their separation. |
| geostationary orbit | A satellite which remains at a fixed point above earth and orbits at the same rate as earth |
| internal energy | The sum of the random distribution of kinetic and potential energies associated with the molecules of it's atoms or molocules |
| specific heat
capacity | The specific heat capacity of a substance is the energy required per unit mass of the substance to raise the temperature by 1 k (1 degree) |
| Boyle’s law; | The pressure exerted by a fixed mass of gas is inversely proportional to its volume, provided the temperature of the gas remains constant |
| Charles Law | v directly proportion to T (V/T =k) |
| Pressure Law | P directly proportional to T |
| Newtons First Law | An object will remain at rest or keep travelling at constant velocity unless it is acted on by an external force. |
| Newtons Third Law | When two bodies interact, the forces they exert on each other are equal in magnitude and opposite in direction. |
| Kepler's third law | The square of the period T of a planet is directly proportional to the cube of the distance r from the sun
T^2 -P to r^3 |
| SHM, A= | A=-W^2Acos(WT) |
| Omega= | 2.pi.f |
| (SHM) x= | Acos(WT) |
| (SHM) V= | -WAsin(WT) |
| What is resonance? | Resonance is the phenomenon that occurs when a physical system is periodically disturbed at the same period of one of its natural frequencies. Occurs when driving frequency = natural frequency |
| Circular motion
v=
a= | 2.pi.r/T
v^2/r |
| When will a object travel in a circular path? | When there is a force perpendicular to the objects velocity |
| Uses of resonance | Cooking - the water molocules forced to vibrate and they absorb energy of microwave radiation. The water gets hotter and the absorbed energy spreads through the food and heats it.
Bridge |
| Random motion aka | Brownian motion |
| Assumptions for ideal gases | Collisions with other particles are perfectly elastic
There are a very large number of particles involved
the time of a collision is negligible compared to time between collisions |
| Assumptions for ideal gases | The volume occupied by the particles is negligible compared to volume of container
Particles are involved in random motion |
| The energy required to change a solid into a liquid at a constant temperature | Latent heat of fusion |
| A liquid into a gas at constant temperature | Latent heat of vaporisation |
| SHM | Force/acceleration is proportional to displacement (from equilibrium
position)
(Resultant force) force/acceleration is (always) towards equilibrium
position (WTTE, e.g. allow fixed point). |
| POWER | Energy/time |
| For any system in resonance | Its natural frequency is equal to frequency of driver
Its amplitude is maximum
It absorbs max energy |
| Why does circular motion no change in speed | Resultant force (F) acts at 90o to motion Fcos90 =0 |
| Potential and kinetic energy changes as tmeperature and state changes | As temperature rise, KE increases, very small PE increase, at constant temp, no change in KE however large PE. |
