Chapter 2

Question 2

When x-rays pass through matter, which interaction results in x-rays being scattered in all directions 60 percent of the time?

Answer 2

C) Compton effect

Question 3

The amount of energy deposited in the teeth or soft tissue by any type of radiation is called the

Answer 3

B) absorbed dose.

Question 4

The unit used to measure the dose equivalent of radiation is the

Answer 4

B) sievert (Sv).

Question 5

The sievert and rem are units of measurement for

Answer 5

C) the comparison of biological effects.

Question 6

A weighting (qualifying) factor is used to determine which of the following?

Answer 6

B) Sievert

Question 7

The wavelength determines the energy and penetrating power of the radiation. The longer the wavelength, the higher the energy of the radiation.

Answer 7

A) The first statement is true. The second statement is false.

Question 8

Matter is defined as the ability to do work and overcome resistance.

Answer 8

FALSE

Question 9

An atom is the smallest part of an element that still retains properties of that element.

Answer 9

TRUE

Question 10

Electrons have a positive charge.

Answer 10

FALSE

Question 11

The innermost electron shell in an atom is the K shell.

Answer 11

TRUE

Question 12

Dental x-rays do not involve the use of radioactivity.

Answer 12

TRUE

Question 13

X-rays travel at the speed of sound.

Answer 13

FALSE

Question 14

Wavelength and frequency are directly related.

Answer 14

FALSE

Question 15

X-rays make the materials they pass through radioactive.

Answer 15

FALSE

Question 16

The photoelectric effect is an all-or-nothing energy loss.

Answer 16

TRUE

Question 17

The Compton effect causes x-rays to be scattered in all directions.

Answer 17

TRUE

Question 18

The number of electrons in the nucleus of an element determines its atomic number.

Answer 18

FALSE

Question 19

Background radiation includes cosmic rays from outer space, naturally occurring radiation from the earth, and radiation from radioactive materials.

Answer 19

TRUE

Question 20

Kinetic energy is the internal energy within the atom that holds its components together.

Answer 20

FALSE

Question 21

The total number of protons in the nucleus of an atom determines the atomic number.

Answer 21

TRUE

Question 22

Energy that travels in a different direction than that of the original x-ray is collectively called ‘secondary radiation.’

Answer 22

TRUE

Question 23

The majority of x-rays produced by dental x-ray machines are formed by general (bremsstrahlung) radiation.

Answer 23

TRUE

Question 24

The electromagnetic spectrum arranges energy types by decay rates.

Answer 24

FALSE

Question 25

X-rays of high energy and extremely short wavelengths are classified as hard radiation.

Answer 25

TRUE

Question 26

Ionizing radiation is energy that is capable of producing ions.

Answer 26

TRUE

Question 27

Electromagnetic radiation is propelled through space as both particles and waves.

Answer 27

TRUE

Question 28

What is defined as anything that occupies space and has mass?

Answer 28

Matter.

Question 29

What are the positively charged particles in the nucleus of an atom called?

Answer 29

Protons.

Question 30

What is the term for atoms that have gained or lost electrons and electrical neutrality?

Answer 30

Ions.

Question 31

What is the name of the process in which unstable elements undergo spontaneous decay in order to become stable?

Answer 31

Radioactivity.

Question 32

What is the term for bundles of energy that travel through space at the speed of light?

Answer 32

Photons.

Question 33

What is the speed of a wave called?

Answer 33

Velocity.

Question 34

When radiation has great penetrating power, what is it called?

Answer 34

Hard radiation.

Question 35

Should you wait 30 seconds after making an exposure before entering the room?

Answer 35

No.

Question 36

People living on the Colorado plateau receive a higher dose of what type of radiation than people living in Philadelphia?

Answer 36

Background.

Question 37

One gray equals how many rads?

Answer 37

100.