Basic principles Flashcards
What is the most abundant atom in the body?
Hydrogen
Where is hydrogen most commonly found at in the body? (2 places)
Fat and water
The _________ contains all of the atoms mass
nucleus
The _______________ is the sum of the protons in the nucleus of an atom.
Atomic number
The ________________ is the sum of the protons and neutrons in the nucleus of an atom.
Mass number
____________ have a positive electrical charge in an atom
Protons
_______________ have a negative electrical charge in an atom
Electrons
______________ have no net charge in an atom.
Neutrons
Atoms of elements with the same number of protons, but a different number of neutrons are called _________.
Isotopes 
The number of electrons is usually the same as the number of ______ in the nucleus.
Protons
This is an atom that has a deficit in the number of electrons compared with protons and causes electrical and stability
Ions
What are the three types of motion present within an atom?
- electrons spinning on their own axis
- Electrons orbiting the nucleus.
- The nucleus itself spinning about its own axis.
MR _____ nuclei are characterized by their tendency to align their axis of rotation to an applied magnetic field
Active
Who came up with the law of electromagnetic induction?
Michael Faraday in 1833
This law refers to three individual forces – motion, magnetism, and charge – and states that if two of these are present, then the third is automatically induced
The law of electromagnetic induction
___________ is the isotope of the hydrogen nucleus that is the MR active nucleus used in clinical MRI
Protium
What is the atomic mass number of protium?
1
The laws of ______________________ state that a magnetic field is created when a charged particle moves.
Electromagnetism
The magnet of each hydrogen atom has a _________ and a _____________ pole of equal strength
north, south
What is a vector?
An entity that has size as well as direction.
What symbol denotes a vector?
arrow
The length of the vector designates what?
size of the magnetic moment
The direction of the vector designates what?
direction of the magnetic moment
This theory describes the properties of electromagnetic radiation in terms of discrete quantities of energy called quanta
 quantum theory
_______ energy nuclei, align their magnetic moments parallel to the external field and are termed ________ nuclei
Low energy, spin-up nuclei
______ energy nuclei align their magnetic moments in the anti-parallel direction and our termed _______ nuclei
High, spin-down
What is the strong static external magnetic field termed in MRI?
B0
