Electromagnetism

SBS1984E

18 Apr 10, 22:27

the figure shows two parallel metal plates AB and CD in an evacuated enclosure. The seperation of the plates is 1.5X10^-2m. X and Y are two slits in CD seperated by 2.5 X10^-2m. A co-linear beam of electrons if different KE is directed at X at an angle of 60 Degrees to the plate CD as shown.

i) Find the KE of electrons entering X that just reaches AB.
ii) Find the velocity of electrons that emerges from Y.

[IMG]http://i40.tinypic.com/23odvr.gif[/IMG]

Ans: 2.1x10^-17J, 5.8X10^6m/s

Could someone help me to get started on this qn. (Prefeably by writing the formula used and the theory behind it. thanks)

SBS1984E

18 Apr 10, 22:28

wee_ws

19 Apr 10, 07:45

Hi,

This is a routine question. Do refer to your notes and textbook for details and examples. Thanks.

Cheers,
Wen Shih

eagle

19 Apr 10, 08:32

I can't see the graphic as my office blocks graphic sharing sites

The formulae you could use are

W = QV = 0.5mv^2

SBS1984E

21 Apr 10, 00:56

Originally posted by wee_ws:

Hi,

This is a routine question. Do refer to your notes and textbook for details and examples. Thanks.

Cheers,
Wen Shih

Maybe its me. But I can't seem to find any worked solutions in my notes which I could use to apply to this qn. This is the only tutorial qn which I have problems with. Anyway, thanks! =)