Raphex 2000

Question 1

the f factor is

Answer 1

• the R to cGy conversion factor
• greatest for high Z materials & low E photons
• is 0.873 in air

Question 2

exposure is

Answer 2

-the charge liberated by photons in a given mass of air

Question 3

1 mSv is equivalent to

Answer 3

• 100 mrem

- 1 mSv=0.001 Sv= 0.1 rem= 100 mrem

Question 4

dose equivalent is greater than absorbed dose for

Answer 4

neutrons

Question 5

an e- is electrostatically ? by an alpha particle

Answer 5

attracted

Question 6

an e- is electrostatically ? by an e-

Answer 6

repelled

Question 7

an e- is electrostatically ? by a positron

Answer 7

attracted

Question 8

an e- is electrostatically ? by a proton

Answer 8

attracted

Question 9

an e- is electrostatically ? by a neutron

Answer 9

not affected

Question 10

charge of a neutrino

Answer 10

• no charge

- negligible mass

Question 11

charge of an alpha particle

Answer 11

• charge of 2

- mass of 4 amu

Question 12

charge of a positron

Answer 12

• charge of +1

- mass of 9.1 x 10^-31 kg

Question 13

charge of a neutron

Answer 13

• no charge

- mass of 1.6 x 10^-27 kg

Question 14

elements which have the same Z but different A are

Answer 14

isotopes

Question 15

the mass # (A) of an atom is equal to the sum of

Answer 15

nucleons

Question 16

when an e- is removed from an atom, the atom is said to be

Answer 16

ionized

Question 17

the t1/2 of a radioisotope is ? than the avg life

Answer 17

less

Question 18

the E absorbed by a mass of air from x or gamma rays per R is

Answer 18

-a constant, 8.7 mGy/R

Question 19

quality factor of 1.25 MeV gamma rays is

Answer 19

1

Question 20

quality factor of 100 keV of x-rays is

Answer 20

1

Question 21

quality factor of 200 keV of neutrons is

Answer 21

20

Question 22

which is not an SI unit: m, kg, sec, rad, Bq?

Answer 22

rad

Question 23

nucleus of a H atom?

Answer 23

proton

Question 24

is emitted during pure beta minus decay?

Answer 24

• antineutrino

- in beta minus decay, a n chgs into a p+, with the emission of a beta minus particle (e-) & antineutrino

Question 25

is created during pair production?

Answer 25

• positron
• pp occurs in the electric fld of the nucleus when a photon of E at least 1.022 MeV disappears & an e- & positron are created

Question 26

initiated fission in U-235?

Answer 26

• neutron

- when a n is absorbed by the nucleus of a U-235 atom, fission occurs

Question 27

charge of an alpha particle?

Answer 27

+2

-consist of 2 p+ & 2 n

Question 28

charge of a neutron?

Answer 28

0

Question 29

charge of an e-?

Answer 29

-1

Question 30

charge of a positron?

Answer 30

+1

Question 31

charge of a photon?

Answer 31

0

-photon carries E but no charge

Question 32

a neutral atom has 6 e- & A f 13. # of n is?

Answer 32

7

-# of e = # of p+, so 13-6=7

Question 33

of e- per gram for H is ? x 10^23

Answer 33

6

Question 34

e- binding E:

Answer 34

• decr with incr distance from nucleus
• is a few eV for the outer e- of an atom
• must be overcome if ioniz is to take place
• binding E incr approx as the square of Z

Question 35

the max # of e- in a shell =

Answer 35

2n^2, where n is the principle quantum #

Question 36

after 10 half lives, the fraction of activity remaining in a source is?

Answer 36

• (1/2)^n

- (1/2)^10

Question 37

effective half life approx equals

Answer 37

physical half life

Question 38

alpha decay most likely occurs in atoms with Z ?

Answer 38

• greater than 82
• A changes by 4
• Z changes by 2

Question 39

an alternative to emission of a characteristic x-ray is

Answer 39

• Auger process
• characteristice xray emitted and undergoes photoelec interaction w/another orbital e-
• E of Auger e- is = to E of characteristic xray less binding E of e-