1) Vp ÷ Np is used to calculate a) Volts per turn on the secondary side b) Primary current c) Secondary turns d) Volts per turn on the primary side 2) In a step down transformer a) The current goes down b) The voltage goes down c) The impedance doubles d) The number of turns increases 3) In a step up transformer a) The current goes down b) The number of turns decreases c) The reactance increases d) The power doubles 4) Transformers are rated by their a) Input properties b) Output capabilities c) Constructional details d) ability to oppose current change of direction 5) Transformers work on the principle of a) Self inductance b) Mutual impedance c) Shared opposition d) Mutual inductance 6) Transformers only work on direct current a) True b) False 7) Transformers need a moving magnetic field to mutually induce a a secondary current in the output side of the transformer a) True b) False 8) Transformer cores are a) Laminated b) Laminations c) Solid d) Fluid 9) Laminated sheets are used to  a) Increase temperture b) Increase cross sectional area c) Reduce eddy currents d) Decrease efficiency 10) When a conductor is cut by lines of magnetic flux a current is induced in the conductor. This is known as a) Electromagnetic induction b) Ferromagnetic induction c) Electromagnetic reduction d) Ferromagnetic production 11) An auto transformer has a) Manageable outputs b) Selectable outputs c) Variable outputs d) Fixed output 12) Eddy currents are a) Unwanted loops of electric current induced within conductors by a changing magnetic field in the conductor b) Wanted loop of electric current induced within conductors by a changing magnetic field in the conductor c) Required loop of electric current induced within conductors by a changing magnetic field in the conductor d) Necessary loop of electric current induced within conductors by a changing magnetic field in the conductor

Transformers

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