Chapter 1- Basic Principles Flashcards
There are two different views of MRI and they are :
Quantum theory and classical
The classical theory focuses more on how the universe works “mechanically”
True
The quantum theory focuses more on the different energy levels of protons and neutrals and electrons
True or False?
True
An atom is organized into “____” which are two or more atoms arranged together?
a molecule
In humans, the most abundant atom is hydrogen.
True or False
True
An atom consists of a central nucleus and orbiting ___
electrons
Protons and neutrons are subcategories of
nucleons
the sum of the protons in a nucleus is called
anomic number
The sum of the protons and neutrons in a nucleus is called the
mass number or atomic weight
When an atom has less neutrons than protons this is called an
isotope
Electrons are particles that spin around the nucleus
True or False
True
Protons have a ____ electrical charge
positive, negative or none
positive
Neutrons have a ____ electrical charge
positive, negative or none
No net charge
Electrons have a ____ electrical charge
positive, negative or none
negative
An atom is considered electrically stable if the number of electrons ____ the number of protons?
equals, is less, is more
equals
How can we alter the balance of an electrically stable atom?
apply energy to knock out the electrons from the atom. This will produce electrical instability.
This is called an ION
the process of knocking out electrons is called
ionization
What are the three types of motion in an atom?
Electrons spinning in their own axis
electrons orbiting the nucleus
the nucleus spinning on its own axis.
If an atom has an even atomic and mass number, (6 protons 6neutrons mass 12), will it have a spin?
no
if they have an even number , half the nucleons spin one direction and the other half another direction which cancels itself out??
How is angular momentum caused?
in nuclei with an odd number of protons, odd number of neutrons, the spin directions are not equal and opposite so it will have a net spin.
What is the large magnetic field of the MRI scanner called?
B 0
What is the magnetic field measured in ?
teslas
The influence of B 0 prouces an additional spin or wobble of the magnetic moment of hydrogen around b0.
True
What is another name for precessional frequency?
Larmor Frequency