- #1
kaotak
Source: Physics and Scientists for Engineers, Ch. 24 #7
A cone of radius R and height h sits on a horizontal table. A uniform electric field parallel to the table penetrates the surface of the cone. What is the flux entering the cone?
Diagram:
(N.B. the dots in the cone are just to give it shape)
E
-->.../.\
-->../...\
-->./...\ <---- cone
-->/____\___________ <- table
The back of the book gives an answer of flux_entering=EhR, which I don't get. I don't see why there isn't a pi in that answer, since the surface area of the face of the cone that's being penetrated certainly does have a pi in it.
My attempt at a solution yields flux_entering=pi*E*h*r/3. Hah, it's close... but not.
EDIT: The field is uniform, I forgot to mention that.
A cone of radius R and height h sits on a horizontal table. A uniform electric field parallel to the table penetrates the surface of the cone. What is the flux entering the cone?
Diagram:
(N.B. the dots in the cone are just to give it shape)
E
-->.../.\
-->../...\
-->./...\ <---- cone
-->/____\___________ <- table
The back of the book gives an answer of flux_entering=EhR, which I don't get. I don't see why there isn't a pi in that answer, since the surface area of the face of the cone that's being penetrated certainly does have a pi in it.
My attempt at a solution yields flux_entering=pi*E*h*r/3. Hah, it's close... but not.
EDIT: The field is uniform, I forgot to mention that.
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