X-Ray Certification Radiation Physics and Protection 3

Question 1

What happens to X-ray beam intensity as the distance from the source doubles?

Accepted Answer

It decreases to one-quarter

Answer

According to the inverse square law, doubling the distance reduces intensity to one-quarter (1/distance²) of the original value.

Question 2

Which type of ionizing radiation consists of two protons and two neutrons?

Accepted Answer

Alpha particle

Answer

An alpha particle is identical to a helium-4 nucleus, consisting of two protons and two neutrons.

Question 3

Lead aprons used in radiography protect against radiation primarily by which interaction?

Accepted Answer

Photoelectric effect

Answer

The high atomic number of lead promotes the photoelectric effect, completely absorbing low-energy scattered X-rays used in diagnostic imaging.

Question 4

What is bremsstrahlung radiation?

Accepted Answer

X-rays produced when electrons are decelerated near a nucleus

Answer

Bremsstrahlung (braking radiation) is produced when high-speed electrons are slowed and deflected by the nucleus of a target atom.

Question 5

What is the annual occupational whole-body effective dose limit recommended by NCRP?

Accepted Answer

50 mSv

Answer

NCRP recommends an annual occupational effective dose limit of 50 mSv (5 rem) for radiation workers.

X-Ray Certification Practice Test