Continuous Charge Distributions

AI Thread Summary
The discussion revolves around calculating the electric field at x = 8.00 m due to a uniformly charged string with a charge density of 9.00 nC/m. The integral setup for the electric field involves the constant k and the charge density λ, but the numerical answer obtained was incorrect. A key point raised was the importance of ensuring the correct units for λ, which contributed to the discrepancy in the results. The participants acknowledged the integral's correct setup but struggled with the final numerical evaluation. Clarifying the units for λ was crucial in resolving the issue.
WarpSpeedo
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Homework Statement



A charge lies on a string that is stretched along an x-axis from x = 0 to x = 3.00 m; the charge density on the string is a uniform 9.00 nC/m. Determine the magnitude of the electric field at x = 8.00 m on the x axis.

Homework Equations


<br /> \int_0^3 kλ/(8-x)^2\,dx <br />

The Attempt at a Solution



k=8.99e9
λ=9

I know k and λ can come out of the integral leaving 1/(8-x^2). which gives me 9.44e-10 which webassign marks wrong.
 
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Your set-up looks fine, but I don't get anything close to the numerical answer you're getting.
 
WarpSpeedo said:

The Attempt at a Solution



k=8.99e9
λ=9

I know k and λ can come out of the integral leaving 1/(8-x^2). which gives me 9.44e-10 which webassign marks wrong.

Are you thinking about the units for λ?
 
Problem was the units for λ. Thanks for your help
 
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