Electric Field of a Conducting Sphere

AI Thread Summary
The discussion revolves around calculating the electric field at a distance of 0.612 cm from the center of a charged conducting sphere, given that the electric field is 485 N/C at 0.206 cm. The participant attempted to solve the problem using the formula E(r) = (1/4πε_0) * (q/r^2) and also tried a ratio method, both leading to the same incorrect result of 1440.874 N/C. Questions were raised about the applicability of the formula outside the sphere and whether the electric field is inversely proportional to distance. Clarification is sought on the correct approach to determine the electric field at the specified distance.
Yosty22
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Homework Statement



At a distance of 0.206cm from the center of a charged conducting sphere with radius 0.100cm, the electric field is 485N/C . What is the electric field 0.612cm from the center of the sphere?

Homework Equations



E(r)=1/4∏ε_0 * qr/R^3
where r is radius of the Gaussian surface and R is the radius of the sphere

The Attempt at a Solution



I tried this two different ways, and they were both the same answer (and both wrong). Firstly, I used the given E-field (485N/C) and plugged it into the above equation and solved for q. Once I solved for q, I used that q with a new distance from the center of the sphere to solve for the new E Field at that position. When I did that, I got that the electric field should equal 1440.874 N/C. I plugged this into my online homework site, and it said I was wrong.

Since that way seemed to be wrong, I tried to just set it up as a ratio. I said that:

(485N/C)/0.00206m = (x N/C)/.00612m

Solving for x, which represents the E Field, I again got 1440.874 N/C.

Any ideas where I might have gone wrong?
 
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Yosty22 said:

Homework Statement



At a distance of 0.206cm from the center of a charged conducting sphere with radius 0.100cm, the electric field is 485N/C . What is the electric field 0.612cm from the center of the sphere?

Homework Equations



E(r)=1/4∏ε_0 * qr/R^3
where r is radius of the Gaussian surface and R is the radius of the sphere

Does this formula apply to the field outside the sphere?

I tried this two different ways, and they were both the same answer (and both wrong). Firstly, I used the given E-field (485N/C) and plugged it into the above equation and solved for q.

How? Using the formula above?

(485N/C)/0.00206m = (x N/C)/.00612m

Is electric field inversely proportional to distance?
 
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