In modern diodes the anode is often brought very close to the cathode so Dial their areas are approximately equal. Assuming the electrons to leave the cathode with zero velocity find the force with which they act on the anode. The current in the tube is i_("sat")=500mA, the anonded voltage is varphi_(a)=600V.

In modern diodes the anode is often brought very close to the cathode

1.	In modern diodes the anode is often brought very close to the cathode so Dial their areas are approximately equal. Assuming the electrons to leave the cathode with zero velocity find the force with which they act on the anode. The current in the tube is i_("sat")=500mA, the anonded voltage is varphi_(a)=600V.
Answer» Solution :The collision of the ELECTRONS with the anode is an inelastic ONE, and this makes it possible to compute the force using formula (17,19) form `oint17.5` NOTING that the current is `F=(imv)/(e)=(i)/(e)SQRT(2evarphim)`

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