unit 3 physics

Cathode, anode, envelope

What is he x-ray tube made of?

Filament, focusing cup, and wiring

What does the cathode consist of?

It’s high melting point, high atomic number, heat-conducting ability, and is difficult to vaporize

Why is Tungsten the metal of choice?

Small coil of thin thoriated tungsten wire

What is the filament?

To provide sufficient resistance to flow of electrons so that the heat produced will cause thermionic emission to occur

What is the function of the filament?

Shallow depression in the cathode assembly designed to house the filament

What is the focusing cup?

Low negative potential

Is the focusing cup provided with a low negative potential or a high negative potential?

Positive

Is the anode the positive side or negative side?

Serves as a target surface for the high-voltage electrons from the filament, thereby becoming the source of the x-ray photons; conducts the high voltage from the cathode back into the x-ray generator circuitry; serves as the primary thermal conductor

What are the three functions of the anode?

To reduce the effective area of the focal spot.

What is the line-focus principle used for?

Filaments

A dual focus tube refers to the tube with two?

Nickel

What is the focusing cup made of?

Space charge effect

As more and more lecterns build up in the area of the filament, their negative charges begin to oppose the emission of additional electrons

An anode that turns on an axis to increase x-ray production while dissipating heat

What is the rotating anode?

Deceleration of electrons

What is the anode responsible for?

Focusing of electrons

What is the focusing cup responsible for?

Source of electrons

What is the cathode responsible for?

Acceleration of electrons

What is the potential difference between b/w cathode & anode when supplied with power