Ch 2, end of chapter questions

d) K shell

____1. Which electrons have the greatest binding energy?

a. N-shell

b. M-shell

c. L-shell

d. K-shell

b) negative

____2. What type of electrical charge does the electron carry?

a. positive

b. negative

c. no charge

d. positive or negative

c) molecule

____3. Which term describes two or more atoms that are joined by chemical bonds?

a. ion

b. ion pair

c. molecule

d. proton

b) atom that loses an electron

____4. Which statement describes ionization?

a. atom without a nucleus

b. atom that loses an electron

c. atom with equal numbers of protons and electrons

d. none of the above

b) radioactivity

____5. Which term describes the process by which unstable atoms undergo spontaneous disintegration in an effort to attain a more balanced nuclear state?

a. radiation

b. radioactivity

c. ionization

d. ionizing radiation

d) nucleons

____6. Which is not a type of particulate radiation?

a. alpha particles

b. beta particles

c. protons

d. nucleons

a) electrons

____7. Which is not a type of electromagnetic radiation?

a. electrons

b. radar waves

c. microwaves

d. x-rays

b) wavelength is the distance between waves

____8. Which statement is incorrect?

a. Velocity is the speed of a wave.

b. Wavelength is the distance between waves.

c. Frequency is the number of wavelengths that pass a given point in a certain amount of time.

d. Frequency and wavelength are inversely related.

a) bc X-rays travel at the speed of light, not the speed of sound

____9. Which statement is incorrect?

a. X-rays travel at the speed of sound.

b. X-rays have no charge.

c. X-rays cannot be focused to a point.

d. X-rays cause ionization.

b) X-rays have more energy then does visible light

____10. Which statement is correct?

a. X-rays are a form of electromagnetic radiation; visible light is not.

b. X-rays have more energy than does visible light.

c. X-rays have a longer wavelength than does visible light.

d. X-rays travel more slowly than does visible light.

b) low-voltage circuit

High-voltage circuit is responsible for accelerating the electrons to high speeds, producing the x-rays themselves, but not directly controlling the filament current.

____29. Which regulates the flow of electrical current to the filament of the x-ray tube?

a. high-voltage circuit

b. low-voltage circuit

c. high-voltage transformer

d. low-voltage transformer

a) step up transformer

____30. Which is used to increase the voltage in the high-voltage circuit?

a. step-up transformer

b. step-down transformer

c. autotransformer

d. step-up circuit

c) x-rays travel from the filament to the target

When the high-voltage circuit is activated, electrons are accelerated from the cathode (filament) towards the anode (target), but the X-rays are actually produced at the anode when the electrons collide with it.

____31. Which does not occur when the high-voltage circuit is activated?

a. The unit produces an audible and visible signal.

b. Electrons produced at the cathode are accelerated across the tube to the anode.

c. X-rays travel from the filament to the target.

d. Heat is produced.

b) positive anode

____32. Which is the location where x-rays are produced?

a. positive cathode

b. positive anode

c. negative cathode

d. negative anode

c) negative cathode

____33. Which is the location where thermionic emission occurs?

a. positive cathode

b. positive anode

c. negative cathode

d. negative anode

____34. Which accounts for 70% of all the x-ray energy produced at the anode?

a. general radiation

b. characteristic radiation

c. Compton scatter

d. coherent scatter

a) general radiation

____35. Which occurs only at 70 kV or higher and accounts for a very small part of the x-rays produced in the dental x-ray machine?

a. general radiation

b. characteristic radiation

c. Compton scatter

d. coherent scatter

b. characteristic radiation

____36. Which describes primary radiation?

a. radiation that exits the tubehead

b. radiation that is created when x-rays come in contact with matter

c. radiation that has been deflected from its path by the interaction with matter

d. none of the above

a. radiation that exits the tubehead

____37. Which describes scatter radiation?

a. radiation that exits the tubehead

b. radiation that is more penetrating than primary radiation

c. radiation that has been deflected from its path by interaction with matter

d. none of the above

c) radiation that has been deflected from its path by interaction with matter

____38. Which type of scatter occurs most often with dental x-rays?

a. Compton

b. coherent

c. photoelectric

d. none of the above

a. Compton

d

____45. Which has the shortest wavelength?

a

____46. Which has the longest wavelength?

a

____47. Which has the lowest frequency?

d

____48. Which has the highest frequency?

protons + neutrons

What determines mass number (atomic weight)?

What determines the atomic number?

The number of protons inside the nucleus (also equals number of electrons in the electron cloud) -this is what makes the atom balanced

What is the strongest/closest electron shell labeled as and what is the weakest?

K, Q