RCES ch1 Exam Questions with All Correct Answers

RCES ch1 Exam Questions with All Correct Answers The flow of electric current is measured in - ANSWER Amperes What is the term used to denote the total opposition to flow of alternating current in a circuit? - ANSWER Impedance What is the most common DC electric power source - ANSWER Battery Electric battery current has a frequency of ? - ANSWER 0 Hz The elimination of vibrations at certain frequencies is accomplished through the use of electronic devices known as? - ANSWER Filters When a DC defibrillator "charges" it stores electrical energy in its: - ANSWER Capacitors EP Lab External defibrillators should be tested by - ANSWER Discharging paddles in to a dummy load The Watt second (or joule) is a unt of: - ANSWER Energy Using Ohms Law, calculate the amount of current drawn by a pacemaker if its lead resistance is 200 ohm's and hte pacing voltage is 1 volt? - ANSWER 5 mA In electrical injury, the pathway way of current most likely to be fatal is : - ANSWER hand to hand For maximum electrical safety, the EKG monitored patient should be ??? and the monitor chasis should be ??? or nonconductive. - ANSWER Ungrounded, grounded In the ICU when recording an intracardiac EKG from a pacing electrode or pericardiocentesis needle, it is safest to ? - ANSWER Use a battery powered monitor When you plug in an electric instrument, you are alarmed when sparks fly from the wall outlet shown, the most likely electrical safety problem is : - ANSWER Machine off-on switch was left on The prefix "centi" corresponds to - ANSWER 1/100 Which prefix listed below is correctly arranged from smallest to largest ? - ANSWER Nano, micro, milli, centi, nano Convert 30 KG into pounds - ANSWER 66 lbs In electrophysiology, the formula for calcuating heart rate is: - ANSWER 60,000 msec/min / time period in miliseconds Calculate the Heart Rate (HR) if the R-R interval is 920 msec> - ANSWER 65 bpm When the heart is insensitive to stimuli and cannot be depolarized by stimulation (such as pacing), it is said to be : - ANSWER Refractory Purkinje and ventricular cells have their own automaticity and intrinsic rate. These lower pacemaker rates are usually suppressed as long as - ANSWER The SA nod rate is fast enough Sympathetic nervous stimulation of the heart primarily affects the heart rate by altering what phase of the SA node AP? - ANSWER Phase 4 Which of the below is NOT one of the 3 things which change the rate (automaticity) of automatic cells? - ANSWER Unidirectional block Concerning the ion transfer across myocardial cell membranes, throughout systole (QT interval): - ANSWER Potassium Leaks out