Term

Definition
A meson is a hadron that is composed of a quark and an antiquark. e.g. a pion or a kaon 


Term

Definition
A baryon is a hadron that is composed of thee quarks.
It has a baryon number of +1. e.g. proton or neutron 


Term

Definition
An antibaryon is a hadron that is composed of three antiquarks.
It has a baryon number of 1. e.g. antiproton or antineutron 


Term

Definition
A lepton is a fundamental particle (cannot be broken down into anything simpler).
It has a lepton number of +1. e.g. electron, neutrino 


Term

Definition
An antilepton is a fundamental antiparticle (cannot be broken down into anything simpler).
It has a lepton number of 1. e.g. positron, antineutrino 


Term

Definition
The critical angle is the angle of incidence, at a dense to rare boundary, which produces an angle of refraction of 90^{o}
. 


Term

Definition
An electron volt is the kinetic energy gained by an electron when it is accelerated across a potential difference of one volt. 


Term

Definition
The angle of incidence equals the angle of reflection. The incident ray, the reflected ray and the normal at the point of incidence are all in the same plane. 


Term
The first law of refraction 

Definition
The incident ray, the refracted ray and the normal at the point of incidence are all in the same plane. 


Term
The second law of refraction or Snell’s Law 

Definition
For rays of any particular wavelength, at the boundary between any two given materials, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant. 


Term
What is the wave equation? 

Definition
c = f x lambda
where f = frequency (Hz); c = speed of light (m/s); lambda = wavelength (m)) 


Term
What is the deBroglie equation? 

Definition
lambda dB = h/p
where: h = Planck constant p = momentum of the particle (= mv where m is the relativistic mass and v is the velocity) lambda dB = deBroglie wavelength 


Term
What is the Einstein electromagnetic wave equation? 

Definition
E = hf = hc/lambda
where: h = Planck constant f = frequency (Hz) c = speed of light (m/s) lambda = wavelength (m) 


Term
What is Einstein’s photoelectric effect equation? 

Definition
hf = psi + ½ mv^{2}
where: hf = the energy of each incident photon (see above)
psi = the work function of the surface (the energy which binds each electron to the surface)
½ mv^{2}= the maximum kinetic energy of an ejected electron (many interact on their way out and therefore have less energy than this!) – you MUST put the word maximum in!!! 

