How do vacuum tubes withstand so much heat during operation?

[maxwell_28]

in vaccum tubes during operation they dissipate lot of power ,my question is how they withstand so much heat,and also the cathode is made of glass?

 

[ptmsl]

Re: vaccum tubes

They withstand heat because they are made of class and metal and not plastic so that nothing melts. Heat is dissipated through the air. Anode and cathode are both made of metal. Only the case (tube) is made of class to seal the vacum inside it.

 

[Borber]

Re: vaccum tubes

Materials used in tubes are nickel for electrodes an wiring, thungsten for heating element, ceramics or mica for support and glass for enclosure. These materials are known as vacuum materials because they do not emit gasses or iones at high temperatures.

 

[puviarasu]

vaccum tubes

Its a variety of vacuum bulb you use in day today life for lighting purpose only difference is that has 2 or 3 more electrodes apart from coil used for amplification.