# Electric power: Quiz

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More interesting facts on Electric power

Question 1: The portion of power flow that, averaged over a complete cycle of the AC waveform, results in net transfer of energy in one direction is known as ________ (also referred to as active power).
Electricity distributionHigh-voltage direct currentElectric power transmissionAC power

Question 2: Devices convert electrical energy into many useful forms, such as heat (________), light (light bulbs), motion (electric motors), sound (loudspeaker) or chemical changes.
Electric heatingStorage heaterFurnaceCentral heating

Question 3: In alternating current circuits, energy storage elements such as inductance and ________ may result in periodic reversals of the direction of energy flow.
MagnetismCapacitanceMaxwell's equationsCoulomb's law

Question 4: In the case of ________ (Ohmic, or linear) loads, Joule's law can be combined with Ohm's law (I = V/R) to produce alternative expressions for the dissipated power:
Electrical conductionElectric currentElectrical impedanceElectrical resistance

Question 5: The result is a scalar since it is the surface integral of the ________.
Maxwell's equationsPoynting vectorLorentz forceMagnetic field

Question 6: Using the ________, the relationship among real, reactive and apparent power is:
Pythagorean theoremTrigonometric functionsTriangleTrigonometry

Question 7: where P is the electric power, V the potential difference, and I the ________.
Electric currentMagnetic fieldElectric chargeMaxwell's equations

Question 8: That portion of power flow due to stored energy, that returns to the source in each cycle, is known as ________.
Electric power transmissionAC powerElectricity distributionHigh-voltage direct current

Question 9: The ratio of real power to apparent power is called ________ and is a number always between 0 and 1.
Switched-mode power supplyTransformerCapacitorPower factor

Question 10: When electric current flows in a circuit, it can transfer ________ to do mechanical or thermodynamic work.
TimeForceEnergyUniverse