Prelim Ems

Question 1

Two types of general radiation

Answer 1

Particulate radiation and electromagnetic radiation

Question 2

Radiation that travels in a space processing either mass or charge or both Radiation usually emitted by radioactive substance Occurs in radiation in motion,Processess high KE (Kinetic Energy), Includes Alpha, Beta, Neutrons and other fragments

Answer 2

Particulate radiation

Question 3

Radiation that travels in a wave form, accompanied by electrical and magnetic field, Radiation that has no mass and no charge, Travels at the speed of light, Includes x-rays and gamma rays, Possesses potential energy

Answer 3

Electromagnetic radiation

Question 4

the distribution of electromagnetic radiation according to energy

Answer 4

Electromagnetic spectrum

Question 5

ranging from the long waves through the broad cast band to short waves and ultra short waves in radar
- used for transmissions of data, via modulation. Television, mobile phones, wireless networking and amateur radio all use radio waves

Answer 5

Radiofrequency

Question 6

these are produced by molecular vibration and the excitation of the outer electrons of the atom. Its heating effect utilized in Physical therapy.

Answer 6

Infrared lights

Question 7

ranging from red, orange, yellow, green and blue to violet
- transmitted by materials such as glass and steel
- can be used in surgery as LASER

Answer 7

Visible light

Question 8

produced by the excitation of our electrons in an atom
- it is higher that the frequency of ultraviolet coming from the SUN. It is induced the human body tp produced Vit. D

Answer 8

Ultraviolet (UV)

Question 9

produced when the fast-moving electron interact with a high atomic level
energy: 1 KeV – 50 MeV Diagnostic: 25 kVp – 150 kVp

Answer 9

X-ray

Question 10

Emitted during Isomeric Transition in radionuclides
no mass, no charge and only in Nuclear EMR.

Answer 10

Gamma ray

Question 11

radiation is not capable of ionization (first 4 in EM spectrum/longer wavelength)

Answer 11

Non-ionizing

Question 12

capable of ionization
a. X-ray
b. gamma ray
c. alpha
d. negatron
e. positron
f. neutron

Answer 12

Ionizing radiation

Question 13

Scattering – a change in direction of photons caused by the interaction between photons and matter
• No ionization, only excitation

Answer 13

Classical/coherent/thomson/rayleigh scattering

Question 14

• Electrons from the outer orbital shell a redeflected by the same electron causing to travel in a new direction as scattered or secondary radiation
• most hazardous to radiation worker due to scatter radiation

Answer 14

Compton Interaction/ Compton scattering /incoherent interaction

Question 15

-first observed by Heinrich Hertz

• occurs when the incident x-ray is totally absorbed during the ionization of an inner shell
• good effect: produces good radiograph or gives contrast

Answer 15

Photoelectric effect

Question 16

occurs in x-rays that have energies greater than 1.022 MeV
- Each electron (negatron or negative electron and positron or positive electron) possesses 0.511 MeV
- important in PET facility
- does not occur in diagnostic radiology

Answer 16

Pair production

Question 17

the photon absorbed by the nucleus and the nuclear fragment is emitted
- the energy required to undergo this interaction is greater than or equal to 7-10 Mev

Answer 17

Photodisintegration