What is the characteristic charge of the cathode side of an X-ray tube?

In an X-ray tube, the cathode is the electrode that emits electrons when heated. This process occurs because the cathode is negatively charged due to a surplus of electrons. When the tube is in operation, the negatively charged cathode repels the electrons towards the anode, where they collide with the anode material to produce X-rays.

The negative charge at the cathode is essential for the operation of the tube, as it establishes the electrical potential difference necessary for the movement of electrons. As electrons are attracted to the positively charged anode, the flow from the cathode to the anode generates the X-rays needed for imaging. Thus, the characteristic charge of the cathode side of an X-ray tube is indeed negative, which directly relates to its role in the tube's functionality.