1. Electromagnetic Radiation

2. MULTIPLE CHOICE

3. 1. The four properties of photons are ____, ____, ____, and ____.
size, shape, spin,
frequency, mass, amplitude, wavelength
frequency, wavelength, velocity, amplitude
refraction, velocity, spin, amplitude

4. ANS: C
The properties of photons are frequency, wavelength, velocity, and amplitude

5. The smallest quantity of any type of electromagnetic radiation is a(n) ____.
Photon
Electron
Neutrino
quark

6. ANS: A
The smallest quantity of any type of electromagnetic radiation is a photon.

7. What is the velocity of all electromagnetic radiation?
8 ´ 103 m/s
2 ´ 108 m/s
3 ´ 108 m/s
4 ´ 103 m/s

8. ANS: C
The velocity of all electromagnetic radiation is 3 ´ 108 m/s.

9. The rate of rise and fall of a sine wave is called its ____.
Amplitude
Frequency
Wavelength
Velocity

10. ANS: B
The rate of rise and fall of a sine wave is called its frequency.

11. A hertz (Hz) is equal to 103 cycles per second 102 cycles per second

12. ANS: D
A hertz is equal to 1 cycle per second

13. What is the electromagnetic wave equation?
c = fë
c = f/ë
c = fv
c = f – ë

14. ANS: A
The wave equation is v = fë

15. The ____ of electromagnetic radiation is constant.
Amplitude
Velocity
Frequency
Wavelength

16. ANS: B
The velocity of electromagnetic radiation is constant.

17. If the wavelength of a beam of electromagnetic radiation increases by a factor of 2, then its frequency must
Double
increase four times
decrease by half
remain constant

18. ANS: C
If the wavelength of a beam of electromagnetic radiation increases by a factor of 2, then its frequency must decrease by half.

19. The intensity of radiation ____ in ____ proportion to the square of the distance of the object from the source.
increases, direct
decreases, direct
increases, inverse
decreases, inverse

20. ANS: D
The intensity of radiation decreases in inverse proportion to the square of the distance of the object from the source.

21. The reduction of radiation intensity due to scattering and absorption is called ____.
Reflection
refraction
Attenuation
Dispersion

22. ANS: C
The reduction of radiation intensity due to scattering and absorption is called attenuation.

23. The intensity of radiation on an object is reduced with distance because the radiation
reduces its velocity
increases in wavelength
Loses its energy
Is spread out over a greater area

24. ANS: D
The intensity of radiation on an object is reduced with distance because the radiation is spread out over a greater area.

25. If the intensity of light from a flashlight is 4 millilumens (mlm) at a distance of 3 feet, what will the intensity be at 6 feet?
0.4 millilumens
1 millilumen
2 millilumen
16 millilumen

26. ANS: B
If the intensity of light from a flashlight is 4 millilumens (mlm) at a distance of 3 feet using the inverse square law, it will be 1 millilumen at 6 feet.

27. The energy of a photon is directly proportional to its
Amplitude
Frequency
Velocity
Wavelength

28. ANS: B
The energy of a photon is directly proportional to its frequency.

29. The mass equivalent of a 100 KeV photon of radiation can be calculated using the
inverse square formula
equivalent Planck equation
relativity formula
Planck quantum equation

30. ANS: C
The mass equivalent of a 100 KeV photon of radiation can be calculated using the relativity formula.

31. X-rays are usually identified by their ____.
Energy
Velocity
Wavelength
hertz

32. ANS: A
X-rays are usually identified by their energy.

33. The lowest energy range of the electromagnetic spectrum is
sound waves
radio waves
gamma rays
microwaves

34. ANS: B
The lowest energy range on the electromagnetic spectrum is radio waves.

35. Gamma rays are produced in the ____ of the atom.
outer electron shell
inner electron shell
nucleus
K-shell

36. ANS: C
Gamma rays are produced in the nucleus of the atom.

37. Photons tend to interact with matter ____ its wavelength.
equal in size to
Larger in size than
Smaller in size than
Unequal in size to

38. ANS: A
Photons tend to interact with matter equal in size to wavelength.

39. Photons with the highest frequencies have the
highest velocity
lowest energy
Longest wavelength
Shortest wavelength

40. ANS: D
Photons with the highest frequencies have the shortest wavelengths. Photons with the highest frequencies have the shortest wavelengths.