Electricity Fundamentals
What is the basic unit of electrical charge, equal to 6.28 × 10¹⁸ electrons?
What is a Coulomb?
What type of current flows in one direction only?
What is direct current (DC)?
What waveform is pure AC and symmetrical?
What is sinusoidal?
What is the most common method of heat transfer in physical medicine?
What is conduction?
What frequency range is used in therapeutic ultrasound?
What is 0.75–3 MHz?
What term describes the opposition to the flow of direct current?
What is resistance?
What type of current rhythmically changes direction?
What is alternating current (AC)?
What waveform is used in high-voltage muscle stimulators and resembles twin spikes?
What is twin pulse?
What physiological effect of heat increases blood flow 1.5–2 times normal?
What is increased circulation?
What effect describes the crystal expanding and contracting when current is applied?
What is the reverse piezoelectric effect?
What analogy is used to explain electrical flow, comparing it to water in pipes?
What is the water/electricity analogy?
What current type is used in iontophoresis for drug delivery?
What is DC?
What term describes the time during which current flows in a single direction?
What is phase duration?
What electromagnetic wave property causes waves to bend as they pass through a substance?
What is refraction?
What term describes the decrease in energy as ultrasound passes through tissue?
What is attenuation?
What is the unit of electrical force required to push 1 amp through 1 ohm?
What is a volt?
What is the term for interrupted electron flow, often used in therapeutic devices?
What is pulsed current?
What law states that the intensity of radiation is inversely proportional to the square of the distance?
What is the inverse square law?
What principle states that optimal radiation occurs when the source is perpendicular to the target?
What is the cosine law?
What type of tissue absorbs ultrasound best due to high protein content?
What are tendons and ligaments?
What law states that current (I) equals voltage (V) divided by resistance (R)?
What is Ohm’s Law?
What current type is used in Russian stimulation for muscle strengthening?
What is polyphasic burst AC?
What law states that waves must be absorbed to be beneficial?
What is the Grotthus-Draper law?
What law explains heat production as proportional to current squared, resistance, and duration?
What is Joule’s Law?
What is the portion of the transducer that produces sound waves?
What is the effective radiating area (ERA) in ultrasound?