## Sunday, March 28, 2010

### Irodov Problem 3.21

The electric field at a distance r from the center of the sphere can be calculated using Gauss law easily as,

E will be directed along the radius vector.

From elementary geometry we can see that,

Hence,

The component of electric field along the z-axis is given by,

Equation (4) basically tells us that the component of electric field along the z-axis does not depend on in other words its same all over the disc section at a distance ro from the center.

The total area of the disc section is given by,

Since the area vector of the disc section is directed along the z-axis, the total flux through this disc section is given by,

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ReplyDeleteall the solutions are great and have used good amount of calculus . by the way thanks , this is really helping me .

ReplyDeletewhy can`t we take our gaussian surface as sphere.. won`t that be much easier

ReplyDeleteE.f is not uniform so gauss approach will no wrk

DeleteWe don't take a sphere because we are asked to find the flux through a plane across the balls section.

Deletehow r°/r = cos theta

ReplyDelete