Line Charge Density of 30uC/7.0m Wire: Answer & Explanation

AI Thread Summary
The discussion centers on calculating the line charge density of a 7.0m wire carrying a uniform charge of 30µC. The correct formula to determine line charge density is λ = Q/L, where Q is the total charge and L is the length of the wire. Participants express confusion over which equations to use, with one user incorrectly attempting to combine formulas. The hint emphasizes that the problem is straightforward, focusing on the relationship between charge and length. Ultimately, the line charge density can be easily calculated by dividing the total charge by the length of the wire.
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Homework Statement



A straight wire 7.0m long carries 30uC distributed uniformly over its length.
What is the line charge density on the wire?

_____ uC/m


Homework Equations



A) E = 2k/lamda /

B) E = kq/r

some other ones?


The Attempt at a Solution



I sub B into a, and got q/2 = 15. But its not correct. Which formula do I use?
 
Physics news on Phys.org
Neither.

Hint: You're given charge and length and asked to calculate charge per unit length...shouldn't be too hard to figure this one out ;)
 

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