Interaction of x-rays with matter

Question 1

What is planks constant

Answer 1

6.62x10^-34

Question 2

What is an alpha particle?

Answer 2

2 protons and 2 neutrons (helium atom)

Question 3

what is the photoelectric effect

Answer 3

when electrons are liberated from metals when illuminated by light of certain frequency

Question 4

define work function as found in the photoelectric effect

Answer 4

minimum energy to liberate elections

Question 5

what equation is used to calculate the minimum kinetic energy of the liberated electron?

Answer 5

1/2mv^2

Question 6

how would you calculate the energy of the photon that liberated an electron?

Answer 6

1/2mv^2 max - work function

Question 7

What is Rayleigh scattering?

Answer 7

incident photo scatters off bound electron in atom, this results in change in direction and NO change in photon energy (ELASTIC)

Question 8

What is Compton scattering?

Answer 8

incident photon scatters off bound electron in atom, this results change in direction and CHANGE in photon energy (INELASTIC)

Question 9

What is pair production?

Answer 9

When electron photon holding greater energy than 1.022 MeV interacts with nucleus to produce an electron and positron with 511keV. The positron then annihilates with the electron to produce 2 photons of 511keV each.

Question 10

What is X-ray fluorescence?

Answer 10

photon removes electron usually from K shell

higher energy bound electron cascades to fill vacancy

difference in shell energies results in emission of photon