FREE RADIOLOGY AND STUDY GAMES ABOUT

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FREE RADIOLOGY AND STUDY GAMES ABOUT

TRANSFORMERS EXAM QUESTIONS

Actual Qs and Ans Expert-Verified Explanation

This Exam contains:

-Guarantee passing score -49 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation

Question 1: Define transformer.

Answer:

An electromagnetic device changing AC from low voltage to high votage, and vice versa, with loss of an appreciable amount of energy.

Question 2: Name the 4 types of transformers.

Answer:

Air core, open core, closed core and shell type.Question 3: If the voltage is stepped up, what happens to the current in the secondary side of the transformer?

Answer:

Decreases Question 4: What device would be used when the milliamperage is set on the control panel?

Answer:

Rheostat

Question 5: How does a transformer change the intensity of alternating voltage and current?

Answer:

Via mutual induction

Question 6: Define eddy current loss.

Answer:

Swirling currents in core by electromagnetic induction.Question 7: Define the formula for calculating secondary current using primary current, #primary turns and #secondary turns

Answer:

Secondary amperage = Primary Amperage (x) #of Primary Turns / # of Secondary Turns Question 8: Define the formula for calculating secondary voltage using primary voltage, # primary turns and #secondary turns.

Answer:

Secondary voltage = Primary Voltage (x) # of Secondary Turns / # of Primary Turns

Question 9: What concept does a transformer work off of?

Answer:

Mutual induction

Question 10: What are the 3 options that allow control of filament current?

Answer:

Choke coil, rheostat and high frequency (HF) circuit.

Question 11: Define closed core.

Answer:

Provides continuous path for magnetic flux; more efficient than air and open cores.

Question 12: Which current (AC or DC) does a transformer operate with?

Answer:

AC

Question 13: When the technologist selects kilovoltage on the control panel, which device is adjusted?

Answer:

Autotransformer

Question 14: What is used as the power source of most modern x-ray machines?

Answer:

3-phase power supply

Question 15: Which current does a transformer work with (AC or DC)?

Answer:

AC

Question 16: Define open core.

Answer:

Has iron core inserted into coil of wire; more efficient than the air core.

Question 17: Which type of current is used with transformers?

Answer:

AC Question 18: Tapping windings of the auto transformer to supply voltage to the step-up transformer is the purpose of what device?

Answer:

kVp Selector

Question 19: Define power loss.

Answer:

The power lost by transformers to heat; usually 5%.

Question 20: The rheostat replaced what device regulating filament current?

Answer:

The choke coil

Question 21: What are the 2 circuits found in an x-ray tube?

Answer:

FILAMENT circuit carrying needed current to heat filament and the TUBE circuit itself.

Question 22: Define autotransformer.

Answer:

Device that varies input voltage to a transformer to control its output voltage.Question 23: Which transformer is the most commonly used in x-ray generating equipment?

Answer:

Closed core transformer

Question 24: Define hysteresis loss.

Answer:

Loss occurring as a result of changing magnetic fields by the AC in the windings. Reduced by laminated silicon steel core.Question 25: Define the formula for calculating secondary voltage using primary voltage, TOTAL # of turns, # of tapped turns.

Answer:

Secondary Voltage = Primary Voltage (x) # of Tapped Turns / Total # of Turns Question 26: What effect does adjusting the filament control have on the production of x-rays?

Answer:

It controls the quantity.

Question 27: Which coil (1st or 2nd) is the output side of the transformer?

Answer:

2nd coil (secondary)

Question 28: Define step-up transformer.

Answer:

When 2nd coil has more turns than 1st coil, and puts out a HIGHER voltage than supplied to it.