Level 3

Question [Ref]

1In a betatron, acceleration of electrons into circular path is achieved by

[AGFA]

a) a rotating magnetic field

b) travelling wave guides

c) the Villard doubling circuit

d) venturi tubes

2Electrostatic or Van de Graff generators have their advantage in that they

[AGFA]

a) operate in the 1 to 2 MeV region

b) have relatively small focal spots

c) have reasonably high output

d) all of the above

3For type-2 exposure devices using a flexible metal drive cable to position the isotope, the isotope capsule is attached to a

[ASNT]

a) zircalloy tube

b) pigtail

c) depleted uranium shield

d) quick disconnect coupling

4Should an isotope camera be found to be leaking radioactive material subsequent to a wipe test

[ASNT]

a) the depleted uranium is to be replaced

b) all exposures since the last wipe test are to be recalled

c) the source is to be destroyed

d) none of the above

5The time it takes to reestablish the electric field intensity required in a G-M counter after the counter has been paralysed by ion avalanche is called

[ASNT]

a) resolving time

b) dead time

c) quench time

d) dwell time

6In LiF dosimetry, energy stored in the material as a result of irradiation is released by

[ASNT]

a) applying a voltage

b) heating

c) illuminating

d) resonating

7In the Van de Graff generator, the heated cathode can be replaced by a gaseous discharge for

[ASNT]

a) electron supply

b) positive ion acceleration

c) coolant purposes

d) prevention of arcing

8The mathematical equation describing the law of electric forces is called

[Burns]

a) Planck's Law

b) Einstein's Law

c) Newton's Law

d) Coulomb's Law9 Inertia is a property of [Burns]

a) matter

b) x-rays

c) neutrinos

d) light10 A single unit of electromagnetic energy is a (an) [Burns]

a) magneton

b) electron

c) phonon

d) photon

11

What is the kinetic energy of an electron ejected from the K-orbit of an atom by photoelectric absorption if the K-orbit binding energy is 500 eV and the photon energy is 1 keV?

[Burns]

a) 0 eV

b) 500 eV

c) 1000 eV

d) 2500 eV12 The equation E=mcý was first derived by [Burns]

a) J.J. Thompson

b) Mme Curie

c) Planck

d) Einstein

13The difference between the mass of the nucleus and the sum of the masses of the particles making up that nucleus is the

[Friedlander]

a) mass coefficient

b) delta force

c) binding energy

d) thermal power factor14 In á decay, the atomic number (Z) changes by [Friedlander]

a) -1

b) 0

c) 1

d) 4

15In positron decay, in addition to the positron a(n) ________ is also emitted.

[Friedlander]

a) neutron

b) neutrino

c) electron

d) alpha particle

16A nucleus having more energy than it has in its ground state is considered to be in a(n) _________ state.

[Friedlander]

a) elevated

b) charged

c) excited

d) isomeric

17If a nucleus is in an excited state, it can return to its ground state by emission of a(n)

[Friedlander]

a) electron

b) gamma photon

c) neutrino

d) alpha particle

18If an excited state nucleus returns to ground state via internal conversion

[Friedlander]

a) an x-ray is emitted

b) an electron is emitted

c) an electron is captured

d) the atomic number(Z) increases

19In most radiography of steel under 50mm thick the largest portion of time spent in producing the finished product (radiograph) is in

[IIW Handbook]

a) setting-up

b) exposure

c) development

d) all of the above equally

20

Inspite of the fact that maximum detectability of nonfusion defects might occur if the x-ray beam is not parallel to the fusion wall, butt welds are usually radiographed such that

[IIW Handbook]

a) the beam is parallel to the film

b) the film is at right angles to the weld

c) the beam is at right angles to the weldd) the beam is at right angles to the film and 45ø to the weld

21Prior to evaluating a component from a radiograph of the part, the radiograph is evaluated for quality based on

[IIW Handbook]

a) latitude

b) density

c) sensitivity

d) all of the above

22When the number of orbital electrons equals the number of nuclear protons in an atom is

[Jaundrell]

a) a positive ion

b) a negative ion

c) in a normal neutral state

d) considered to be meta-stable

231 milliampere second is equivalent to ________ coulombs

[Jaundrell]

a) 0.001

b) 0.01

c) 1

d) 1000

24Two 2 ohm resistors connected in parallel result in a total resistance of ________ ohms.

[Jaundrell]

a) 0.25

b) 0.5

c) 1

d) 4

25If 2 æF capacitors are connected in series the resultant capacitance is

[Jaundrell]

a) 0.25æF

b) 0.5æF

c) 1æF

d) 4æF

26Resistance in most conducting wires tends to decrease with increasing

[Jaundrell]

a) density

b) vacuum (negative pressure)

c) mass

d) temperature

27Grenz rays, typically used in x-ray diffraction work, have energies in the range of

[Training Manual 3]

a) 1-2MeV

b) 500-1000 keV

c) 50-100 keV

d) 5-20 keV

28A radiation induced alteration in the DNA of a cell that does not kill the cell but alters characteristics of the off-spring of that cell is

[Training Manual 3]

a) mutation

b) sterilization

c) clonogenesis

d) metamorphosis

29 Ionizing radiation refers to[Training Manual 3]

a) electromagnetic radiation

b) corpuscular radiation

c) radiation from the useful beam onlyd) any EM or corpuscular radiation that is capable of producing ions

30X-radiation that is emitted from an x-ray tube that does not make up the useful beam is

[Training Manual 3]

a) wasted

b) scatter radiation

c) secondary radiation

d) leakage radiation