Chapter 13 Flashcards
Notability
1
Q
Conduction occurs through
A
Physical contact, causing collision of atoms & molecules
2
Q
Convection is
A
Heat transfer due to the movement of matter from one location to another
3
Q
Heat transfer involving electromagnetic waves is called
A
Radiation
4
Q
All objects emit energy via
A
Radiation
5
Q
What causes the highest amount of heat loss?
A
Radiation
6
Q
Waves are a periodic
A
Disturbance or motion
Are essentially the movement of energy
7
Q
What are the 2 types of waves?
A
Transverse & Longitudinal
8
Q
Transverse waves are composed of
A
Up & down movement
Particles in the medium move perpendicular (up & down) to the wave direction
EMR waves
9
Q
Longitudinal waves are composed of
A
Back & forth movement along the direction of the wave
Particles move forward, parallel to the direction of the wave (propagation)
Sound waves
10
Q
Frequency
A
Waves per second; measured in cycles per second
Called Hertz (Hz)
11
Q
Wave length
A
Distance from one wave to the next (the top)
12
Q
Amplitude
A
Height of the wave
13
Q
Speed
A
Measured in meters/second
14
Q
Reflection waves reflect
A
Off a medium at the same but opposite angle
The angle of incidence is the angle at which a wave strikes a medium
15
Q
Refraction is the
A
Redirection due to contact with a new medium; Humans use refraction to redirect light in the cornea to relay images to the brain
16
Q
Diffraction is the
A
Spreading or scattering; bending around an object
17
Q
Absorption or interference is when
A
Waves interfere with other waves or be absorbed by matter
When a wave interfere, amplitudes are additive
18
Q
Constructive interference is when
A
The crest of one wave passes through the crest of another wave or the trough of one wave passes through the trough of another wave, resulting in a greater wave
19
Q
Sound waves are
A
Pressure fluctuations that deviate from ambient pressure
20
Q
Sound pressures are measured on a
A
Logarithmic decibel scale to narrow the wide range of amplitudes audible to the human ear
21
Q
Sound waves are longitudinal waves that
A
Propagate through matter at varying speeds determined by the medium in which they are passing
22
Q
In the absence of matter, there are
A
No sound waves
Sound waves do not exist in a vacuum& only travel through matter
23
Q
Sound waves above the auditory limit of the human ear (20kHz) are known as
A
Ultrasound
24
Q
Ultrasound is made possible by
A
Piezoelectric crystals that act as signal generators & transducers
25
What causes the crystals to generate an electric current?
Mechanical stresses (change shape)
26
The Doppler effect describes the
Change in frequency of a propagated wave from a moving object
27
EMR is composed of what 2 waves
Electric & Magnetic
(oscillates in unison perpendicular to one another)
28
Electric & Magnetic waves both possess
Frequency & Amplitude & may be reflected, refracted, diffracted or absorbed
29
The unique wave properties of EMR include its
Composition, velocity & independence of transport by matter
30
An example of electromagnetic radiation with matter is
Visible light
31
Materials that absorb EMR increase their
Vibration energy
32
Speed equation
Wavelength x Frequency
OR
Wavelength over time
33
Electromagnetic waves are produced when
Charged particles are accelerated
Composed of mutually perpendicular electric & magnetic fields, which are constantly varying but remain in phase
Can travel through a vacuum such as space
34
Wavelength is the
Distance between adjacent peaks or troughs & measured in meters
35
The period is the
Time required for a wave to repeat itself measured in seconds
36
The frequency describes the
Number of wave cycles that occurs in 1 second, measured in Hertz
37
If the wavelength increases
The frequency must decrease
38
Light exhibits properties of both
Waves & particles
39
The energy of electromagnetic radiation is inversely
Proportional to the wavelength & directly proportional to the frequency
40
Photons have
No mass
They are pure energy
41
The energy of EMR is
Directly related to its frequency
42
Higher frequencies correspond to
Higher energies, although the velocity remains constant & does not change depending on frequency
43
What is the first law of thermodynamics
Law of conservation of energy
Energy cannot be created nor destroyed
44
Energy & matter are
Interchangeable
Matter can be converted to energy
45
What is the Atomic Mass Number?
Total number of protons & neutrons in the nucleus
46
The atomic number defines an elements
Chemical properties
47
Nuclide is the technical term for
Isotope
48
An isotope emphasized
Chemical properties
49
Nuclides emphasize
Nuclear properties
50
Some isotopes have too many neutrons to be stable. What will happen?
Are considered to be decayed & release neutrons
Known as radioisotopes or radioactive isotopes
51
What is Radioactive decay?
The spontaneous process by which an unstable nucleus goes from a higher level of energy to a lower level of energy
The emission of energy in the form of ionizing radiation
52
Elements with atomic numbers greater than 83 are
Unstable & will undergo radioactive decay
53
What are the 5 types of radioactive decay
Alpha
Beta minus
Positron
Electron capture
Gamma Ray emission
54
In radioactive decay, a decaying nucleus is called the
Parent
The nucleus produced is called the daughter
55
Alpha particles consist of
2 protons & 2 neutrons
56
Alpha decay is characterized by the
Emission of an alpha particle from the parent nucleus
Energy is released in the form of kinetic energy
57
What must equal in radioactive decay equation?
Total mass number on left & right
58
Why does alpha decay occur?
It is energetically favorable & results in the Alpha decay daughter being in a lower energy state
59
Alpha decay is more common among very
Heavy nuclei where the repulsion between the positively charged protons in the nucleus makes elimination of an alpha particle energetically advantageous
60
Beta decay results in the
Mass number remaining constant while the atomic number changes
Nucleus either loses or gains a proton
61
What are the 3 types of Beta decay?
Beta minus
Positron
Electron capture of decay
62
Beta minus decay is when a
Neutron and the atom’s nucleus turn into a proton, an electron & an antineutrino
Energy, the electron, & the antineutrino are emitted
63
Antineutrinos are a very
Weak interactive particle with an extremely small mass
64
What can make the nucleus unstable?
When the nucleus has too many protons & the repulsion between the positively charged protons makes it unstable
65
What will happen when the nucleus has too many protons?
The transformation of a proton into a neutron and well as a positron & a neutrino
66
The mass numbers of the parent & daughter are identical but the
Atomic numbers are different
67
What is electron capture decay?
When an inner orbital electron is absorbed within the nucleus resulting in a proton being converted to a neutron along with the emission of a neutrino
68
What is Auger Effect?
The process of creating another vacancy until there is an emission of an orbital electron
69
What is Gamma Ray emission?
When electrons fall from higher energy states to lower ones
Extra energy is emitted as visible light
70
Which rays have the smallest wavelengths & most energy?
Gamma Rays, which cannot be reflected
71
Decay rate is a way to
Quantify radioactive decay & is equal to the number of radioactive decays occurring per unit of time
72
Exponential decay describes the process of
Reducing an amount by a consistent percentage rate over a period of time
73
Exponential decay is when the amount of something is
Decreased at a rate proportional to its current value
Something decreases greatly at first & then becomes much slower later
74
Half lives of nucleotide allows us to
Predict the time required for a large number of atoms to decay until only half of the initial atoms are left
They are an example of exponential decay
75
Non ionizing radiation is absorbed by
Matter & causes rotation, vibration or excitation within electron in atoms or molecules
76
Non ionizing radiation lacks
Sufficient energy to remove any electrons, so no ions are formed
77
Ionizing radiation included
Breaking covalent bonds in molecules
78
Ionizing radiation is more
Destructive than non ionizing radiation (but they still have harmful effects)
79
Which energies are ionizing?
Alpha particles
Beta particles
Gamma rays
Xrays
80
What can be used to determine the age of very old geologic formations with radiometric dating
Primordial nucleotides
81
Cosmogenic nucleotides are formed
When cosmic rays from space interact with matter
Include carbon 14
82
What happens to the carbon 14: carbon 12 ratio when an organism dies?
Decreases due to carbon 14 decay
83
Gamma rays can penetrate
Thick layers of matter without significantly interacting with the material
84
What particles interact with matter as they pass through resulting in a large amount of energy deposition
Alph
Beta
85
What is Roentgen?
The unit used to quantify the amount of radiation exposure to X-rays & Gamma rays
86
The quantity of energy from radiation that is absorbed is called the
Absorbed dose which has units of Joules per Kilogram & is called the gray
87
Which particles have a large deposit of energy, charge & mass?
Alpha
88
A large amount of interaction between radiation & water will happen between
Cells, products including ions, reactive free radicals, & atoms & molecules in excited states
Can lead to DNA damage directly or indirectly
89
Which cells have high sensitivity
Ones that divide frequently such as bone marrow & embryos & the male gonads
90
Cells that are not replaced quickly also exhibit
Enhanced sensitivity to radiation
91
What is CT
Transmission computerized
92
What is SPECT
2 dimensional image
Single Photon Emission CT
93
What is PET scan
When a positron is injected & can measure blood flow, oxygen use & glucose metabolism
94
What is the challenge with PET scan
How to target the diseased tissue without adversely affecting healthy tissue
95
X-rays are
Ionizing radiation & are higher in the frequencies of the EMR spectrum
Have high energy & have the ability to ionize atoms & cause DNA damage & be neurogenic
96
What 3 factors should be implemented?
Distance
Barriers
Exposure Time
97
The greatest exposure to xray is
Directly infront of the beam generator
Intensity also significantly decreases with distance from the source
6 feet
98
Intensity equation
1 divided by distance squared
99
Waves represent the
Propagation of energy from a source
100
Energy decreases as it
Moves away from the source
101
Strength of energy is inversely proportional to
The square of its distance from the original source
102
Inverse square law applies to
Pressure waves, electricity, light, & radiation
103
Magnetism is a
Force between electrical currents
104
Flowing charged particles move
Energy along a current & also disrupt & alter the surrounding environment
105
MRI Zone 1
Access area
106
MRI Zone 2
Patient screening & preparation
107
MRI Zone 3
Restricted area
Screened MRI
Patients & MRI
Personnel only
108
MRI Zone 4
Danger
109
MRI uses
A continuous magnetic field to uniformly realign the spin of protons within the hydrogen atoms of water
110
People with implantable objects are
At risk for thermal & traumatic injury
