Principles of Electricity and Electrical safety Physical Agents (1)

Electricity and Electrical safety Physical
Agents
Net movement of electrons is an - CORRECT ANSWER-Electrical Current

Difference in concentration of electrons between two points - CORRECT
ANSWER-Potential difference

Current is measured in - CORRECT ANSWER-Amperes (A)

Having two oppositely charged conductors, electrons flow from neg to pos -
CORRECT ANSWER-Polarity

Anode and cathode charge - CORRECT ANSWER-Anode +
Cathode -

Electrical force that moves charged particles - CORRECT ANSWER-Voltage

Voltage is measured in - CORRECT ANSWER-Volts (V)

Opposition to the flow of charged particles - CORRECT ANSWER-Resistance

Measure of electrical power and its calculation - CORRECT ANSWER-Watt
W=VxA

Materials that permit free movement of electrons - CORRECT ANSWER-Conductors

Resistance of conductors - CORRECT ANSWER-Little / Low resistance

Materials that resist the flow of electrons - CORRECT ANSWER-Insulators

Resistance of insulators - CORRECT ANSWER-High resistance

Primary biological resistance to current flow - CORRECT ANSWER-Skin
Skin prep is important

Fat contains 14% water meaning it is a - CORRECT ANSWER-poor conductor

Blood composed largely of water and ions meaning it is - CORRECT ANSWER-The
best conductor

, Muscle is this percentage of water - CORRECT ANSWER-75%, contraction
dependent on ion movement

Bone is extremely dense with about 5% water making it the - CORRECT
ANSWER-poorest biological conductor

Current flow though tissue (lowest to highest) - CORRECT ANSWER-Bone < Fat <
Muscle < Blood

Types of wave-form (DAPIP) - CORRECT ANSWER-Direct current
Alternating Current
Pulsed Current
Interferential Current
Premodulated current

Direct Current - CORRECT ANSWER-Continuous unidirectional flow of charge
particles (monophasic)
Leaves a charge on the tissue

Examples of direct current - CORRECT ANSWER-Iontophoresis
Stimulating denervated muscles
Wound healing

Alternating current - CORRECT ANSWER-Continuous bidirectional flow of charged
particles (biphasic)
Equal ion flow in both directions (always - to + pole )
No pulse charge remains in tissue f

Difference in Russian protocol to alternating current - CORRECT ANSWER-Break
in-between currents ( 10 msec on, same off, same on)
Not "continuous"

Pulsed current - CORRECT ANSWER-Series of pulses of short duration separated
by periods of no current flow

Types of biphasic pulsed current - CORRECT ANSWER-Symmetric
Balance Asymmetric
Unbalance asymmetric

Monophasic pulsed current - CORRECT ANSWER-Always DC current
Always leaves a charge in the tissue
Includes High Volt Pulsed Current (only to wound care)