EM1 Practice Exam with 100% correct answers(latest update)

Current is the flow of electrons Voltage is a force that moves electrons Resistance is A. present in all conductors B. essentially infinite in insulators C. useful to control the flow of current D. all of the above Power is voltage times current In a circuit, if voltage is raised and resistance is held constant, current will Increase In a circuit, if resistance is raised and voltage is held constant, current will Decrease True or false: in the absence of voltage, current will not flow. True True or false: in the presence of voltage, current will always flow. False In a circuit, electrons flow: from the negative terminal of a voltage source to the positive terminal In the positive current convention, current is imagined to flow: from the positive terminal of a voltage source to the negative terminal The universally acknowledged authority on electrical safety standards is: the National Electrical Code from the NFPA A current of 0.02 amp or more through the body is dangerous because: it causes muscles to lock up According to the electrical code, the highest DC voltage that is safe to handle directly is: 50V According to the code, the highest AC voltage that is safe to handle directly is: 30V According to the code, in wet conditions the highest voltage that is safe to handle directly is: 12V AC or DC A voltage that is higher than those listed above: must be contained so people cannot accidently come in contact with it A current of 0.1A through the body: is lethal When working with voltages higher than those listed in questions 2-4, you should: work with one hand in your pocket An inverter: A. converts a low voltage to a high voltage B. is often designed to run on batteries C. can create a dangerous voltage inside a piece of equipment D. all of the above In AC power wiring, the black wire is: Hot In AC power wiring, the chassis ground wire is: Green A hot chassis unit: is directly connected to one side of the power line A unit that is not normally hot-chassis may become hot-chassis through: failure of a component such as the hash filter To be sure a unit is not hot-chassis, before working on it one should: measure the resistance between both sides of the power plug and the chassis Does turning off a unit's power switch or pulling a fuse reliably disconnect the circuitry from the power cord? No Phantom voltage is: voltage that's stored in power supply capacitors Before working on a unit, it should be unplugged and power supply capacitors discharged to: the unit's chassis