Equipment Operation & Patient Preparation (Electrical Functions) Flashcards
What are amps (amperage)?
Not the same as amplitude
The amount of electrical current measured in amps
What is alternating current?
An electric current that reverses direction in a circuit at regular intervals.
What is frequency? What is it measured in?
What frequency is usually used in North America?
Number of cycles per second
Hertz
60 Hz
What is direct current?
An electric current flowing in one direction only. (Example: A battery.)
What is electrical potential?
What is another word for electrical potential?
A measure of work required by an electric filed to move electric charges.
Also called voltage.
What is amplitude?
Amplitude is measured in ___ or ___.
The height of a waveform.
Measured in millivolts or microvolts.
What does gain do?
Increases or decreases signal size of the amplifier signal
What is sensitivity?
The higher the sensitivity setting, the (smaller / larger) the deflection.
The amount of output to a given input voltage.
Smaller
What are watts?
A measure of the amount of work done by a certain amount of current at a certain voltage.
What is impedance?
What’s another word for impedance?
Total opposition to current. Also called resistance.
(Metals=low resistance)
(Wood = high resistance)
What is capacitance?
The ability to store a charge (B-23)
How do you calculate capacitance?
Capacitance = Charge / Volts
The use of extension cords is not recommended. If they are used, must have these three things:
They must be medium or heavy duty.
Must contain certification label
Don’t coil the cord. (Fire hazard)
When using extension cords, the plug must have ___ or the prongs must be ___.
Must have three prongs.
If two prongs, it must be polarized (one prong is wider than the other).
What is Ohm’s Law?
Current (I) = Voltage / Resistance
/V\
/ \_\_ \
/ I x R \
(Remember there's two of these pyramids and V is on top for both of them.)
