X-ray Tube

What is required of a metal target in an x-ray tube?

1)Ability to conduct heat 2) High atomic number 3)High melting point

How fast do high speed anodes rotate?

10,000RPM

How many kilovolts is equal to 75,000 volts?

75kV

What is the area of the x-ray target called that is struck by electrons?

Actual focal spot

In what unit is filament current measured?

Amperage

As kilovoltage is applied, the electrons are accelerated toward which part of the x-ray tube?

Anode

What types of primary radiation is produced when the x-ray tube boltage is below 70?

Bremsstrahlung

What is the negative terminal x-ray tube?

Cathode

Which part of the x-ray tube has the filament wires and focusing cup?

Cathode

Electrons travel in an x-ray tube from ___ to ___.

Cathode, Anode

What is the purpose of the anode in an x-ray tube?

Decelerates electrons

What are the x-ray tubes called that have 2 filament wires?

Dual focus tubes

Which is the smallest? -Space charge -Actual focal spot -Effective focal spot -Target

Effective Focal Spot

Which is not related to the other? -Rotor -Target -Filament -Tungsten Disk

Filament

Which parts make up the cathode end of the x-ray tube?

Filament and focusing cup

The formula, mA x kVp x time(s) is for what?

Finding heat units

What is used to focus the electron stream toward the target of the anode?

Focusing cup

What is the purpose of a window in an x-ray tube?

For the emmision of x-rays

When electrons strike the target of an x-ray tube, most of their energy is converted to what?

Heat

What determines the quantity of electrons that will be accelerated across the x-ray tube?

Heating of the filament

Which kVp and mAs combination produce the least load on an x-ray tube?

High kVp, low mAs

As the x-ray tube gets older, what happens to the temperature of the filament?

Increases

What type of motor drives the rotating anode?

Induction

Which of the following is filtration that is manufactured into the x-ray tube?

Inherent Filtration

Why is an x-ray tube immersed in oil?

Insulation

What increases the penetrating power of the x-ray tube?

Kilovoltage

When electrons strike the anode of an x-ray tube, how much of their energy is converted to x-rays?

Less than 1%

What causes the pitting of the x-ray tube target?

Moderate overloading of the tube

If used properly, will an x-ray tube last forever?

No, the filament wire will break

What is the definition of off focus radiation?

Photons that are not produced at the focal spot

The small craters in the target of a used anode of an x-ray tube are known as what?

Pitting

During an exposure, what electrical charge is placed on the anode?

Positive

Why is that x-ray tube encased in a lead housing?

Prevent leakage radiation

What is NOT needed to produce x-rays?

Rotating anode

What would NOT be found on the control panel?

Rotor button

According to the line focus principle, the effective focal spot is ___ than the actual focal spot.

Smaller

During thermoniac emission a cloud of electrons surround the filament. What is the electron cloud called?

Space charge

What effect will increasing the kVp have on the production of x-rays?

Their energy will increase

What is the process of "boiling off" electrons called?

Thermionic Emission

Why is an x-ray tube made of Pyrex glass?

To better withstand heat

As electrons are accelerated across the x-ray tube, they are referred to as what?

Tube current

The filament wires in radiographic tubes are made from what metal?

Tungsten

The target of an x-ray tube is made of what metal?

Tungsten

In a modern, rotating anode x-ray tube, what coats the tungsten disk?

Tungsten rhenium alloy

When will a space charge be present in the x-ray tube?

Whenever the rotor engaged

What causes most x-ray failures?

excessive heat