ASVAB Electronics

ASVAB Electronics Electricity - General term for the variety of phenomena resulting from the presence and flow of electric current Volts Amperes (amps) Ohms - 3 ways Electricity is measured Volts - Measure the difference of potential between 2 points Amperes (amps) - Measure the number of electrons that move past a specific point in 1 second (i.e. electrical currents) Ohms - Measure resistance, including anything that could limit the flow of electrons Current - Electrical ___ occurs when electrons move from one place to another. Conductors (e.g. copper, silver, water) - A substance, body, or device that conducts electricity; allows the electrons to move freely. Insulators (e.g. rubber, wood) - A material of such low conductivity that does not easily allow the flow of electrical current to pass through it; discourages electrical current Watt - This measures power, the rate at which electrical energy is consumed or transformed into another type of energy, such as light or heat Power - The rate at which electrical energy is consumed or transformed into another type of energy, such as light or heat Watt-hour - This is the amount of energy used in 1 hour at a rate of 1 watt. Kilowatt-hour - The amount of energy used in 1 hour at a rate of 1,000 watts(i.e.1-kilowatt) True - True or False Most electricity is measured in kilowatt-hours Wattage x Time (expressed in hours) - To find watt-hours multiply ___ by ___. 10 kilowatt-hours - How many kilowatt-hours is enough energy to run a 10,000-watt speaker system for 1 hour? 2 hours - 10 kilowatt-hours is enough energy to run a 5,000-watt air conditioner for how long? 10 hours - 10 kilowatt-hours is enough energy to run a 1,000-watt waffle iron for how long? Circuit - The path of an electrical current Open - When there is literally an open space in the circuit that prohibits current from flowing Short - When the open space of a circuit has been closed to allow current to flow Voltage - The difference of the pressure between 2 points in a circuit (sometimes called voltage drop or difference of potential) True - True or False To see what the voltage is anywhere in a circuit, you have to compare the voltage at that point to ground Ground (e.g. base of a lamp, chassis of a car) - Any part of a circuit (or other object that has electricity running through it) that measures 0 volts Voltmeter or multimeter - Measures voltage in a circuit Voltmeter - An instrument used for measuring electrical potential difference between two points in an electric circuit (i.e. voltage) A voltmeter has 2 leads. To measure voltage, you place one lead somewhere in the circuit and one lead at another location in the circuit. The voltmeter tells you what the voltage is between those 2 points. - How to use a voltmeter: Cell - A storage compartment for electricity in a battery that has a specific voltage. True - True or False You can figure out the number of cells a battery has by dividing the voltage of the battery by the volts. Electrical current - The flow (rate of flow) of electrons in a conductor coulombs (C), which measure charge. - Current flow can be expressed in terms of ___. Coulomb - The amount of electricity provided by a current of 1 ampere flowing for 1 second. True - True or False If 1 coulomb (about 6,241,500,000,000,000,000 electrons) flows past a specified point in 1 second, that's a flow rate of 1 ampere (amp, abbreviated A).