Whole Topic Flashcards
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Velocity
The rate of change of displacement
Acceleration
The rate of change of velocity
Work done
A measure of the energy transferred during a process
Law of consrvation of energy
Energy can neither be created or destroyed, just changes from one form to another.
Momentum
The product of an object’s mass times it velocity
Law of conservation of momentum
In the absence of external forces the total momentum before a collision is equal to the total momentum after a collision
Elastic collision
An elastic collision is one in which kinetic energy is conserved.
Inelastic collision
An inelastic collision is one in which kinetic energy is lost
Newton’s first Law
An object will remain at rest or continue at constant speed in a straight line unless acted on by an unbalanced force
Newton’s second law
The acceleration of an object is proportional to the unbalanced force acting on it and inversely proportional to its mass. (a = F/m)
Newton’s third law
If a body A exerts a force on body B then body B exerts an equal and opposite force on body A.
Newton
One Newton is the force required to give an object of mass 1kg an acceleration of 1ms-2.
Impulse
Impulse is the average force on an object multiplied by the time of contact (Ft)
Impulse is also equal to the change in momentum of the object.
Universal law of gravitation
The force of attraction between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. F = Gmm/r2
Gravitational field strength
Gravitational field strength is the force (or weight) per unit mass experienced at a point in a gravitational field. (g = F/m)
Time dilation
The time between events measured by a stationary observer will be greater than that measured by an observer moving with the events.
Length contraction
The length between events measured by a stationary observer will be less than that measured by an observer moving with the events.
Doppler effect
The frequency of radiation observed depends on the velocity of the source relative to the observer.
Redshift
Redshift is the term given to the change in frequency of light emitted by stars, as observed from earth, due to the stars moving away from us. The spectra of these stars is shifted towards the red end of the spectrum.
Hubbles Law
For distant objects, the further away from Earth the object is, the faster it is moving away from Earth. v = Hod where v = recessional velocity and Ho = Hubbles constant.
Dark Matter
Type of matter proposed to make up for the missing mass in the Universe.
Dark energy
Type of energy proposed to make up for the missing energy in the Universe.
This is to account for the fact that the rate of expansion of the Universe is increasing.
Cosmic Microwave Background (Radiation)
Observed background radiation present everywhere in the Universe. It provides evidence to support the Big Bang theory
Anti-matter
Each matter particle has an antimatter particle equivalent with an opposite charge but identical mass.
Baryon
A particle made up of 3 quarks
Meson
A particle made up of 2 quarks
Boson
Force mediating particle
Fermion
Matter particle
Hadron
a particle made up of quarks
