Particles Flashcards
Charge of an electron
-1.6x10^-19 C
Charge of a proton
1.6 x 10^-19 C
Charge on a neutron
0C
Mass of proton and neutron
1.67 x 10^-27 kg
Mass of an electron
9.11 x 10^-31
Specific charge
Charge per unit mass C/kg
Speed of light in a vacuum
3.0 x 10^8 ms^-1
Planck’s Constant
6.63 x 10^-34 Js
Wave speed equation
c=f lambda
Photon energy equation
E = hf
The electron volt eV
The work done when one electron is moved through a potential difference of one volt.
1eV = 1.6 x 10^-19 J
The strong force is repulsive up to…
0.5 fm
The strong force is attractive in the range…
0.5 fm - 3 fm
The strong forces acts to stabilise the nucleus in 2 ways
- It provides an attractive force to counter the electrostatic repulsion of the protons.
- As the nucleons get closer together the force becomes repulsive to force them back apart so prevent them from coalescing.
Alpha decay
A-4
Z-2
Releases an alpha particle
Mono-energetic from a given isotope
Beta minus
Neutron -> proton + electron + anti electron neutrino
Beta plus
Proton -> neutron + positron + electron neutrino
4 fundamental forces
- gravity
- electromagnetism
- strong force
- weak force
Muons decay into electrons
Muon (minus) -> electron + muon neutrino + anti electron neutrino
Weak decay
Mediates strong nuclear force
Pion/ pi meson
Lightest baryon
Stable when free
All baryons decay into this
Proton
Stability of the neutron
Not stable when free
Half life approx 15 minutes
Can be stable in Nucleus
Photoelectric equation
hf = phi + Ek max
De Broglie equation
Lambda = h/mv
Wave particle duality of an electron
Wave: -electron diffraction
Particle: - acceleration
- interactions with magnetic and electric fields
Wave particle duality of light
Wave: diffracts/ refracts/ interferes
Particle: photoelectric effect
