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Ch.4
Electromagnetism
Question | Answer |
---|---|
Changes in direction, establishes and collapses in the magnetic field | AC current |
devices used for changing the potential of alternating currents involving two coils primary and secondary | Transformers |
voltage from the first primary coil is increased to the secondary coil | step-up transformer |
voltage from primary coil is decreased to the secondary coil | step-down transformer |
Calculates the voltage and the number of turns in the secondary and primary coils | Transformer Law: Vs/Vp = Ns/Np |
Calculates current AMPERAGE (I) in combination with the transformer law | Ohm's Law Is/Ip =Vp/Vs |
Amps _______ as voltage _______ in step-up | decrease, increases |
Caused by highly induced voltages and massive amounts wires in step-up transformers | power loss |
copper loss, resistant to current flow | I2R loss |
lag loss due to fluctuating AC current | Hysteresis |
current opposition to its original | Eddy current |
Name four core configurations | Air,Open,Closed,Shell-Type |
Which core configurations most commonly used in cray generators? | Shell-Type |
Primary/Secondary coils are connected in series rather than insulation in this type of transformer | autotransformer |
Three major transformers in an x-ray circuit | Autotransformer, High-voltage step-up transformer, Filament Step-down transformer |
decreases incoming line voltage to heat the tube filament | Filament Step-down transformer |
this type of transformer raises incoming line voltage needed for xray production | High-voltage step-up transformer |
varies incoming line voltage | Autotransformer |
Device capable of accumulating and storing electrical charge, and commonly used in portables | capacitors |
Uses only half of incoming alternating current to be converted to pulsating direct current | half-wave rectification |
Use of four rectifiers(4 diodes) in the secondary coil of step-up transformer | full-wave rectification |
Converts negative part of AC sine wave to positive current, flowing in one direction | full wave rectification |