LRA 222 FINAL EXAM NEWEST -

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LRA 222 FINAL EXAM NEWEST -

EXAM NEWEST 250 QUESTIONS AND CORRECT

DETAILED ANSWERS ( VERIFIED ANSWERS )

|ALREADY GRADED A+

What is the target of the rotating and usually coated with? - ANSWER- Tungsten

What is the most common cause for tube failure? - ANSWER- tungsten vaporization

High capacity tube rotors revolve at _____ rpm. - ANSWER-

10,000

How many filaments does a dual focus tube have? - ANSWER- 2

Is the filament on the positive or negative side of the tube? - ANSWER- Negative

What is a filament made of? - ANSWER- Tungsten

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What are the components of the anode? - ANSWER- stator and rotor

What are the components of the cathode? - ANSWER- filament and focusing cup

With the rotating anode the focal spot becomes what? - ANSWER- Focal track

Why does the focusing cup keep the electrons together? - ANSWER- Repelling them into a group bc negative repels negative

What is the stator made of? - ANSWER- electromagnets

What happens to the tube if you prep the rotor, but do not expose an x-ray often? - ANSWER- Damage

Where is the main power switch located? - ANSWER- primary circuit

Where is the primary side of the high voltage transformer found? - ANSWER- primary circuit 2 / 4

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Where is the timer circuit found? - ANSWER- primary circuit

Where is the step down transformer found? - ANSWER- filament circuit

What is the purpose of a line compensator? - ANSWER- Measures and stabilizes voltage

What is the purpose of the rectifier? - ANSWER- Convert AC to DC

What is the purpose of the filament circuit? - ANSWER- Boils electrons/ thermionic emission

What is the primary purpose of a step down transformer? - ANSWER- Coverts high voltage to low voltage

To produce x-rays, does a cathode require positive or negative charge? - ANSWER- Negative

What is tube current? - ANSWER- Rate of flow of electrons

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AEC - ANSWER- automatic exposure control

What does AEC control? - ANSWER- the quantity of radiation reaching the IR

When it comes to the circuit, where is the x-ray tube located? - ANSWER- Secondary circuit

Who developed the electromagnetic theory in 1800? - ANSWER- James Clark Maxwell

Does electromagnetic radiation have mass? - ANSWER- No

What effect does mAs have on brightness? - ANSWER- no effect

What happens with digital imaging when the mAs setting is too high? - ANSWER- Over exposed patient

What is the result of using excessive kVp with a digital IR? - ANSWER- Increase scatter

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