1 Matter and radiation Flashcards
nucleon
neutron and proton in the nucleus
isotope
atoms of an element with different numbers of neutrons and the same number of protons
nuclide
a type of nucleus with a particular number of protons and neutrons
atoms
proton = charge 1.6 x 10-19
mass 1.67x10-27
neuton= charge 0
mass 1.67x10-27
electron = charge -1.6x10-19
mass 9.11x10-31
specific charge
mass
the electron has the biggest specific charge
the strong nuclear force
repels 0-0.5 fm (so the nucleus doesn’t merge together)
attract 0.5-4 fm
alpha radiation
2 protons and 2 neutrons
beta radiation
1 electron
photons
packet of electromagnetic waves
power of beam = nhf
made up of an electric field and a magnetic field at 90 degrees to each other
electron volts
energy requires accelerating an electron through a pd of 1V
1eV = 1.6x10-19 1MeV = 1.6x10-13
particle and antiparticle
they have the same mass
annihilation
particle + antiparticle = 2 photons
pair production
photons = particle + antiparticle
(B+ decay)
proton
neutron
W+
B+
V(neutrino)
(B- decay)
neutron
proton B- W- _ V
Proton and antineutrino
_
p and V
W+
neutron
B+
Neutron and Neutrino
N and V
W-
P
B-
two protons
P and P
Y
P
P
electron capture
P and e-
N
V
W+
electromagnetic wave
a wavepacket or photon consisting of transverse waves electric and magnetic waves in phase and at right angles to each other
photoelectric effect
emission of electrons from a metal surface when the surface is illuminated by light of frequency greater than a minimum value known was the threshold frequency
theshold frequency
minimum frequency of light that can cause photoelectric effect
brain imaging
-gamma radiation is used
used on people like stoke patients
T = tomography
How was a neutrino found?
Existence of the neutrino was hypothesised to account for the conversion of energy in beta decay
Particles and antiparticles
Every type of particle, there is corresponding antiparticle
Photon energy
E = hf = hc /λ
