In a cathode ray tube, what is the number of electrons that reach the fluorescent screen controlled by?

Answer by  ScottHorn (232)

In a cathode ray tube the electrons directed at the screen are emitted by an electron gun. This electron gun consisted of a cathode, which is heated, and an anode, which directs and focuses the electrons. The number of electrons is determined by the temperature of the cathode, as well and the voltage difference between the cathode and anode.

Answer by  mb (5482)

I think that you mean the number of photons that reach the fluoscent screen. The number is controlled by the amount of electons flowing acroos the tube (the milliamperage) and the power of the electrons (the kilovoltage). These strike the anode of the tube and the photons are released. The actually number is in the trillions.

Answer by  willard (874)

The number of electrons ejected by the cathode is controlled by the temperature of the cathode and by its shape. The more sharply pointed the cathode, the stronger the electric fiels near it surface, and the larger the forces that act on the electrons. The number that hit the screen also depends on the density of gas in the tube.

Answer by  MPX (171)

In a CRT, the light (electrons) are controlled by the outer coils of magnet wire, this wires create different magnetic fields to control the electrons.