National Dental Assisting Examining Board (NDAEB) Practice Exam

What is the positive electrode inside the x-ray tube called?

1. Filament

2. Cathode

3. Anode

4. Target

The correct answer is: Anode

The positive electrode inside the x-ray tube is known as the anode. In the context of an x-ray tube, the anode serves a crucial role in the production of x-rays. When electrons, which are emitted from the negative electrode (cathode), accelerate towards the anode due to the high voltage applied, they collide with the anode material. This interaction produces x-rays when the kinetic energy of the electrons is converted upon impact. The anode is typically made of a material with a high atomic number, such as tungsten, which is effective in producing x-rays due to its efficient energy conversion properties and high melting point. This allows the anode to withstand the heat generated by the electron impact during x-ray production. The filament, on the other hand, is a component of the cathode and is responsible for emitting electrons when heated. The target refers to the specific area on the anode where the electrons strike, but it is not the name of the electrode itself. Understanding the distinction between these components is important in the context of radiographic imaging and the operation of x-ray equipment.