basic physics Flashcards
memorized
of the following types of electromagnetic energy, which has the shortest wavelength?
Diagnostic rays
which of the following are accurate statements regarding the characteristics of x-rays ?
1.they are highly penetrating and invisible
3. they travel in straight lines at the speed of light
the term for a continuous path for the flow of electrical charges from the power source through one or more electrical devices and back to the source is :
Electrical circuit
The smallest possible unit of electromagnetic energy is the
photon
The common unit of measure for the potential difference across an x-ray tube is the :
VOLT
the frequency of alternating current (AC) delivered by electric utilities in the united states and Canada is
60 HERTZ
The purpose of transformer is to :
increase or decrease voltage
which electron shell in the atom is most important for the production of x-rays?
K shell
Electrons are held in place around the nucleus of the atom by an
binding energy
when an atom gains or loses an electron it is called
ion
the process of converting AC to DC is called
Rectification
one of the most important elements in radiology that is used to create x-rays Is
tungsten
x-rays cause ionization in the human body this has a negative effect on the body .
TRUE
if a transformer has 100 turns on the primary side and 25 turns on the secondary side, it is a step down transformer
TRUE
A Transformer with 500: 1 ratio would be a
step-up transformer.
True
x-rays can cause cancer.
true
how does wavelength affect the usefulness of an x-ray beam ? the shorter the wavelength the more penetrating the beam
six characteristics of x-rays
- have no mass
- are highly penetrating and invisible
- Are electrically neutral
- Are polyenergetic and heterogeneous
- travel in straight lines at the speed of light , can ionize matter.
- produce biologic changes in tissues produce secondary and scatter radiation.
current : amperes (A)
potential difference : VOLTS (v)
Electrical resistance : ohms
convert 40000volts to kilovolts ; 40 kvp
0.5 amperes to milliamperes : 500 mA
what is the duration of an electrical cycle in the united states? An electrical impulse?
Electrical cycle= 1/60 sec
electrical impulse = 1/120 sec
what is the primary purpose of a Transformer
to change the voltage
Electromagnetic induction
the process by which an electric current in one circuit influences a current to flow in a second circuit.
ammeter
measures electrical current
VOLT meter
measures electrical potential
Alternating current
current changes polarity from negative to positive at regular intervals
kilovolt = equal to 1000 VOLTS
1000 volts
rectification
process of changing AC to DC
Ampere (A)
unit to measure the rate of current flow in a circuit
mA milliampere
equal to 0.001 A ( 1/1000 A)
VOLT
unit to measure potential difference
current
quantity of electrons flowing in a circuit
what is the device that produces the high voltage need for x -ray production
transformer
when an electrical current uses its magnetic field to create a secondary current , this process is called
electromagnetic induction
step up transformer
500 primary side and 1 in the secondary side
